Prostaglandin I2 derivatives

ABSTRACT

A novel prostaglandin I 2  derivative selected from a prostaglandin I 2  having a halogen atom on the carbon atom corresponding to the 7-position of natural prostaglandin I 2  and having a cycloalkylene group in the α-chain, and its esters and salts.

TECHNICAL FIELD

The present invention relates to novel prostaglandin I₂ derivatives.More particularly, the present invention relates to prostaglandins I₂having a halogen atom, particularly a fluorine atom, on the carbon atomcorresponding to the 7-position of natural prostaglandin I₂ and having acycloalkylene group in the α-chain, and their esters and salts, whichwill hereinafter be referred to generally as prostaglandin I₂derivatives. Further, the present invention relates to pharmaceuticalcompositions containing such prostaglandin I₂ derivatives as activeingredients. In this specification, prostaglandin may sometimes bereferred to simply as PG.

BACKGROUND ART

Natural PGI₂ is a local hormone product in vivo mainly at theendothelium of arterial vessels, and it is an important factor forcontrolling cell functions in vivo by its strong physiologicalactivities such as an anti-platelet activity and a vasodilatingactivity. There has been an attempt to use it directly as a drug (P. J.Lewis, J. O. Grandy et al, Clinical Pharmacology of Prostacyclin RavenPress, N.Y., 1981). However, natural PGI₂ has in its molecule a vinylether bond which is susceptible to hydrolysis and is readily deactivatedunder a neutral or acidic condition. Thus, because of its chemicalinstability, it can not be regarded as a good compound for a drug.Therefore, studies have been made to develop chemically stable syntheticPGI₂ derivatives having physiological activities equal to natural PGI₂.Among them, there is a report on a case wherein a fluorine atom wasintroduced to various sites ("Journal of Synthetic Organic Chemistry,Jpn", vol 42, 794 (1984), and 7-fluoro-PGI₂ derivatives having fluorineintroduced at the 7-position have been reported (Japanese UnexaminedPatent Publications No. 171988/1982 and No. 243079/1985). Further, PGI₂derivatives having a cycloalkyl group introduced to the ω-side chain inorder to improve the pharmacological effect and stability, have beenreported (Japanese Unexamined Patent Publication No. 163365/1984).However, there has been no report on PGI₂ having a cycloalkyl groupintroduced to the α-side chain or on derivatives thereof.

DISCLOSURE OF INVENTION

The present inventors have conducted extensive researches and as aresult, have found that by introducing a cycloalkyl structure to theα-side chain of PGI₂ and introducing a halogen atom on the carbon atomcorresponding to the 7-position of natural PGI₂, strong inhibitoryactivities on platelet aggregation and anti-anginal activities can beobtained, and yet these compounds have high stabilities. As the halogenatom, a fluorine atom is preferred, and the number is preferably one.

Thus, the present invention provides a novel prostaglandin I₂ derivativeselected from a prostaglandin I₂ having a halogen atom on the carbonatom corresponding to the 7-position of natural prostaglandin I₂ andhaving a cycloalkylene group in the α-chain, and its esters and salts.

The present invention also provides a pharmaceutical composition forprophylaxis and treatment of circulatory diseases, which contains such aprostaglandin I₂ derivative as an active ingredient.

DETAILED DESCRIPTION OF THE INVENTION

In PGI₂ in the present invention, the bivalent hydrocarbon moiety in theα-chain corresponding to the trimethylene group at the 2- to 4-positionof natural PGI₂ is preferably a C₃₋₈ cycloalkylene group, or a bivalenthydrocarbon group having a methylene group or a dimethylene group bondedto at least one bond of such a cycloalkylene group.

The hydrocarbon group corresponding to the n-pentyl group at the 16- to20-position of natural PGI₂ is a monovalent organic group of varioustypes, including an alkyl group, a substituted alkyl group, a cycloalkylgroup, a substituted cycloalkyl group, an aryl group and a substitutedaryl group. A alkyl group, a cycloalkyl-substituted alkyl group and acycloalkyl group are preferred. Particularly, preferred is a C₅₋₈ linearor branched alkyl group.

In the present invention, preferred is a prostaglandin I₂ derivative ofthe following formula (I): ##STR1## In the PGI₂ derivative of theformula (I) of the present invention, R₁ is a substituted orunsubstituted C₁₋₁₀ alkyl, alkenyl or alkynyl group, or a substituted orunsubstituted 5- or 6-membered cycloalkyl group. The C₁₋₁₀ alkyl,alkenyl or alkynyl group is preferably methyl, ethyl, n-propyl,iso-propyl, n-butyl, n-pentyl, n-hexyl, 1,1-dimethylpentyl,2-methylhexyl, 1-methyl-3-pentenyl, 1-methyl-3-hexenyl,1-methyl-3-pentynyl or 1-methyl-3-hexynyl. More preferably, it is a C₅₋₉alkyl group. Particularly preferred among them is a n-pentyl group, an-hexyl group, a 2-methylhexyl group or a 1,1-dimethylpentyl group.

The substituted or unsubstituted 5- or 6-membered cycloalkyl group ispreferably a cyclopentyl group, or a cyclohexyl or cyclopentyl groupsubstituted by e.g. methyl, ethyl, propyl, butyl, pentyl, phenoxy,trifluoromethyl or a trifluoromethylphenoxy.

R² is a hydrogen atom, a C₁₋₁₀ alkyl group or a cation.

This C₁₋₁₀ alkyl group may be a linear or branched alkyl group such asmethyl, ethyl, n-propyl, iso-propyl, n-butyl, sec-butyl, tert-butyl,n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl or n-decyl. Among them, amethyl group and an ethyl group are preferred.

The cation may be an ammonium cation such as NH₄ ⁺, tetramethylammonium, monomethyl ammonium, dimethyl ammonium, trimethyl ammonium,benzyl ammonium, phenethyl ammonium, morpholinium cation, monoethanolammonium, tris cation or piperidinium cation; and alkali metal cationsuch as Na⁺ or K⁺ ; or a bivalent or trivalent metal cation such as1/2Ca²⁺, 1/2Mg²⁺, 1/2Zn²⁺ or 1/3Al³⁺. Particularly preferred as R² is amethyl group or a sodium ion.

Each of R³ and R⁴ which may be the same or different, is a hydrogen atomor a protecting group. Various protecting groups may be employed. Forexample, a silyl group having three substitutents such as alkyl groups,aryl groups or aralkyl groups, an alkanoyl group, a tetrahydropyranylgroup, a tetrahydrofuranyl group, a benzoyl group, or a methoxyethoxygroup may be employed. Among them, a trialkylsilyl group is preferred,wherein the three alkyl groups may be the same or different, andparticularly preferred is that at least one of the alkyl groups is analkyl group having at least two carbon atoms. Specifically, adimethyl-t-butylsilyl group, a triethylsilyl group or adiphenyl-t-butylsilyl group may, for example, be mentioned. Particularlypreferred is a dimethyl-t-butylsilyl group.

One of X¹ and X² is a hydrogen atom, and the other is a halogen atom.The halogen atom is a fluorine atom or a chlorine atom. Particularlypreferred is a fluorine atom. It is particularly preferred that X¹ is afluorine atom, and X² is a hydrogen atom.

k, l, m and n are integers of from 0 to 6, provided that 1≦l+m≦6 and0≦k+n≦4.

l and m represent numbers relating to the number of members constitutingthe ring of the cycloalkylene group and the position of the bonds of thecycloalkylene group. Namely, l+m+2 represents the number of carbon atomsconsisting the ring of the cycloalkylene group. The smaller numericalvalue of l and m represents the positions of the bonds of thecycloalkylene group. For example, when the smaller of l and m is 0, suchrepresents a 1,2-cycloalkylene group, and when the smaller of l and m is1, such represents a 1,3-cycloalkylene group.

Each of k and n represents the number of methylene groups bonded to thebond of the cycloalkylene group. Each of k and n may be 0.

Each of l and m is preferably 0, 1, 2 or 3. Particularly preferably, l+mis from 1 to 4. Namely, the cycloalkylene group is preferably from acyclopropylene group to a cyclohexylene group. Each of k and n ispreferably 0, 1 or 2. In this case, k+n is preferably from 0 to 2.Particularly preferably, k+n is 0 to 1.

Further, the length of the carbon chain corresponding to thetrimethylene group at the 2- to 4-positions of natural PGI₂, i.e. eachof k+l+n+2 and k+m+n+2, is preferably at most 6. Particularlypreferably, the smaller of k+l+n+2 and k+m+n+2 is from 2 to 4, and thelarger of them is from 3 to 5.

The compound of the formula (I) of the present invention has in itsstructure from 6 to 10 asymmetric carbon atoms and thus has variousstereoisomers. The compound of the present invention includes all suchstereoisomers, optical isomers and mixtures thereof.

The PGI₂ derivatives of the present invention can be synthesized byvarious methods. A feature of the PGI₂ derivative of the presentinvention resides in that it has a cycloalkylene group in the α-chain.It can be prepared by a method for the preparation of otherwise known7-haloPGI₂. Otherwise, it is also possible to employ usual methods forthe preparation of PGI₂.

One of such methods is a method for preparing it by cyclization of thecorresponding 7-haloPGF₂ α or 7-halo-5,6-dehydroPGF₂ α (5-, 6- and7-positions represents positions corresponding to natural PGI₂, the sameapplies hereinafter) (for this method, please refer to Scheme 1 and itsdescription given hereinafter). Further, there is a method wherein Coreylactone is used as a starting material for the synthesis. Further, it isalso possible to synthesize PGI₂ having a cycloalkylene group in theα-chain, followed by halogenation of the 7-position to obtain the PGI₂derivative of the present invention.

When Corey lactone is used as a starting material for the preparation ofthe PGI₂ derivative of the present invention, it is usual to employ amethod wherein the ω-chain is firstly introduced, and then the α-chainis introduced. However, the α-chain may be introduced first.Introduction of the halogen atom may also be conducted at any optionalorder with respect to the introduction of these two chains. For thesynthesis wherein Corey lactone is used as a starting material, thereare a method wherein the halogen atom is introduced before theintroduction of both the α-chain and the ω-chain, and then the remainingchains are introduced, and a method wherein the α-chain and the ω-chainare introduced first, and then the halogen atom is introduced (a methodvia 7-haloPGF₂ α or 7-halo-5,6-dehydroPGF₂ α). For the former method,there are a method via 7-haloPGF₂ α and a method not via 7-haloPGF₂ α.

Now, three embodiments (1) to (3) will be described for the methodwherein Corey lactone is used as a starting material, and the ω-chain isintroduced first, followed by the introduction of the α-chain. In theseembodiments, the halogen atom is a fluorine atom.

(1) An ω-chain-attached Corey lactone is fluorinated to obtain thecorresponding fluoroketone. The fluorination may be conducted by amethod wherein a hydroxyl group is firstly introduced to the carbon atomone which a fluorine atom is to be introduced, and then the fluorineatom is introduced by a fluorinating agent such as dimethylamino sulfurtrifluoride, or by a method wherein the lactone is converted to anenolate, which is then reacted with XeF₂.

Then, an α-chain is introduced to the fluoroketone. A basic reaction tointroduce an α-chain to a lactone by direct methylene conversion isknown (T. Okazoe, K. Takai, K. Oshima, K. Utimoto, J. Org. Chem., 52,4410, 1987), and this method can be employed. Further, it is alsopossible that a fluorolactone is reduced to a fluorochemiacetal, then anα-chain is introduced by a Wittig reaction to obtain the after-mentionedcompound (VII) (7-fluoroPGF₂ α), followed by cyclization as describedhereinafter to obtain the desired product. For the Wittig reaction,reference may be made, for example, to E. J. Corey, N. M. Weinshenker,T. K. Schaaf, W. Huber, J. Am. Chem. Soc., 91, 5675, 1969.

(2) An ω-chain-attached Corey lactone is reduced to a lactol, then anα-chain is introduced by a Wittig reaction, and then a hydroxyl group isintroduced at the 7-position to obtain the after-mentioned compound(VII). Thereafter, from the compound (VII), the desired compound can beprepared as will be described hereinafter.

(3) Cyclopentane carbaldehyde is prepared from a ω-chain-attached Coreylactone (an ω-chain-attached cyclopentanone may also be used as thestarting material), and acetylide which will form an α-chain, is reactedthereto to obtain 7-hydroxy-5,6-dehydroPGF₂ α. Then, this compound isfluorinated (see the fluorination in Scheme 1 given hereinafter) toobtain the after-mentioned compound (IV) (7-fluoro-5,6-dehydroPGF₂ α),from which the desired compound can be synthesized.

Now, a synthetic method via 7-haloPGF₂ α or 7-halo-5,6-dehydroPGF₂ α,and a synthetic method for 7-haloPGF₂ α or 7-halo-5,6-dehydroPGF₂ αwithout using Corey lactone as a starting material, will be described indetail. In the description, the halogen atom at the 7-position is afluorine atom.

The compound of the formula (I) of the present invention can be producedby the process represented by the following flow sheet (Scheme 1).##STR2## wherein R¹, k, l, m and n are as defined above with respect tothe formula (I), R²¹ is a C₁₋₁₀ alkyl group, and each of R³¹ and R⁴¹which may be the same or different, is a protecting group other than atrimethylsilyl group. ##STR3## wherein R⁵ is a protecting groupdifferent from R³¹ and R⁴¹ other than a trimethylsilyl group, and R¹,R²¹, R³¹, R⁴¹, k, l, m and n are as defined above with respect to theformula (II). ##STR4## Wherein R¹, R²¹, R³¹, R⁴¹, R⁵, k, l, m and n areas defined above with respect to the formula (III). ##STR5## Wherein R¹,R²¹, R³¹, R⁴¹, k, l, m and n are as defined above with respect to theformula (II). ##STR6## Wherein R¹, R²¹, R³¹, R⁴¹, k, l, m and n are asdefined above with respect to the formula (II). ##STR7## Wherein R¹,R²¹, k, l, m and n are as defined above with respect to the formula(II).

Namely, the compound of the formula (II) is converted to the compound(III) by the method disclosed in the applicants' earlier application(Japanese Unexamined Patent Publication No. 10551/1986), followed byfluorination (compound (IV)), removal of a protecting group (compound(V)), cyclization (compound (VI)), removal of a protecting group and, ifdesired, hydrolysis or salt-formation, whereby the compound of the aboveformula (I') can be obtained. In the above formula (III), R⁵ is atri(C₁₋₇)hydrocarbonsilyl group other than a trimenthysilyl group, or agroup capable of forming an acetal bond together with the oxygen atom ofthe hydroxyl group. As the tri(C₁₋₇)hydrocarbonsilyl group, atriethylsily group is particularly preferred. As the group capable offorming an acetal bond together with the oxygen atom of the hydroxylgroup, a 2-tetrahydropyranyl group or a 2-tetrahydrofrany group isparticularly preferred. Each of R³¹ and R⁴¹ is a protecting groupdifferent form R⁵ other than a trimethylsilyl group and is preferably atri(C₁₋₇)hydrocarbonsilyl group. As the tri(C₁₋₇)hydrocarbonsilyl group,a tri(C₁₋₄)alkylsilyl group such as a t-butyldimethylsilyl, adiphenyl(C₁₋₄)alkylsilyl group such as a t-butylidiphenylsilyl group, ora tribenzylsilyl group may, for example, be mentioned as a preferredgroup, Particularly preferred is a t-butyldimethylsilyl group. Thefluorination of the compound (III) can be conducted by a known method(Japanese Unexamined Patent Publications No. 32718/1985 and No.227888/1984). Namely, it can preferably be conducted by an amino surfertrifluoride type fluorinating agent such as piperidino sulfurtrifluoride or diethylamino sulfur trifluoride in a fluorinatedhydrocarbon type solvent such as 1,1,2-trichloro-1,2,2-trifluoroethaneor trichlorofluoromethane. By the reaction with such fluorinating agent,a compound of the formula (IV) is obtained, and such a compound can beconverted to a compound of the formula (V) by a known reaction forremoval of a protecting group. The removal of a protecting group cansuitably be conducted by using e.g. acetic acid, p-toluene sulfonicacid, pyridinium p-toluene sulfonate or a cation exchange resin, as acatalyst, and using e.g. water, methanol or ethanol, or tetrahydrofuran,ethyl ether, dioxane, acetone or acetonitrile in the presence of water,methanol, ethanol or the like, as the solvent for reaction. The reactionis conducted usually within a temperature range of from -78° C. to +50°C. for from 10 minutes to 3 days. The compound of the formula (V) can beconverted to a compound of the formula (VI) by a cyclization reaction.For this cyclization reaction, a known technique can basically beemployed. For example, it can be conducted in accordance with a methoddisclosed in J. Amer. Chem. Soc., vol 104, p 5842-5844 (1982). Namely,the cyclization reaction can be conducted by cyclization by means ofmercury trifluoroacetate, followed by hydrogenation with a hydrogenatingagent. Otherwise, it can be conducted in accordance with the methoddisclosed in Japanese Unexamined Patent Publication No. 120377/1987.Namely, the cyclization reaction can be conducted by cyclization bymeans of phenyl selenenyl chloride, followed by removal of the phenylselenenyl group by means of a reducing agent such as tributyltinhydride. Otherwise, it can also be conducted in accordance with themethod disclosed in U.S. Pat. No. 4,612,380. Namely, the cyclizationreaction can be conducted by hydrogenating the compound of the formula(V) by a known method (Tetrahedron Letters, vol 25, p 1383-1386 (1984))to convert it to a compound of the following formula (VII): ##STR8##wherein R¹, R², R³, R²¹, R³¹, R⁴¹, k, l, m and n are as defined above,and cyclizing it by means of N-iodosuccinic acid imide or iodine,followed by removal of hydrogen iodide by means of a base such as1,8-diazabicyclo[5,4,0]-7-undecene (DBU). The compound of the formula(VI) thus obtained may be subjected to a reaction for removal of aprotecting group and/or a hydrolyzing reaction and/or an esterificationreaction and/or a salt-forming reaction, as in the case requires, toobtain a prostaglandin I₂ derivative (I') of the present invention. Forthe removal of a protecting group for the hydroxyl group (the reactionfor removal of a protecting group), a fluorine-type reagent such astetrabutyl ammonium fluoride, cesium fluoride, hydrofluoric acid orhydrogen fluoride/pyridine can be used. Tetrabutyl ammonium fluoride isparticularly preferred. As the solvent for reaction, tetrahydrofuran,ethyl ether, dioxane, acetone or acetonitrile can, for example, be used.The reaction can suitably be conducted usually within a temperaturerange of from -78° C. to +50° C. for from 10 minutes to 3 days. Thereaction for hydrolysis of the ester group at the 1-position can beconducted by a usual method, for example by hydrolyzing it with anaqueous solution or a water-alcohol mixture solution of e.g. sodiumhydroxide, potassium hydroxide or calcium hydroxide, or with analcohol-water mixture solution containing sodium methoxide, postassiummethoxide or sodium ethoxide. Otherwise, the hydrolysis may be conductedby treatment with an enzyme such as lipase in water or in a solvantcontaining water within a temperature range of from -10° C. to +60° C.for from 10 minutes to 24 hours. Post treatment and purification afterthe hydrolytic reaction can be conducted in a usual manner afterneutralization with an acid such as dilute hydrochloric acid or oxalicacid.

The compound having a carboxyl group formed by the above mentionedhydrolytic reaction is then further subjected to a salt-formingreaction, as the case requires, to obtain the corresponding carboxylate.The salt-forming reaction is known per se and can be conducted bysubjecting the carboxylic acid and a substantially equivalent amount ofa basic compound such as sodium hydroxide, potassium hydroxide or sodiumcarbonate, or ammonia, trimethylamine, monoethanol amine or morpholine,to a neutralization reaction by a usual method. The carboxylate candirectly be obtained by the above-mentioned reaction for hydrolysis ofthe ester.

The esterification of the hydroxyl group can readily be accomplished bya usual method of reacting an acid anhydride or an acid halide in thepresence of a base, i.e. by reacting acetic anhydride, acetyl chlorideor benzoyl chloride in the presence of a base such as pyridine ortriethylamine (Shinjikken Kagaku Koza, vol 14-II, 1002-1027, compiled byJapan Chemical Association, Maruzen K.K.).

There is no particular restriction as to the method for preparing thecompound of the formula (II) which is the starting material of thepresent invention. However, it can be prepared, for example, by twomethods (a) and (b) shown in the following Scheme 2. ##STR9## wherein Mis an organic metal species (such as copper, nickel, zirconium, zinc oraluminum), and R¹, R²¹, R³¹, R⁴¹, k, l, m and n are as defined abovewith respect to the formula (II).

Here, the method (a) can be conducted in accordance with the methoddisclosed in Tetrahedron Letters, vol 23, 4057 (1982). In (b), themethod of conducting 1,4-addition of an alkenyl metal reactant to anenone and capturing it with a trimethylsilyl group is known (J. Am.Chem. Soc., vol 97, 107 (1975)), and the obtained silylether can beconverted to a compound of the formula (II) in accordance with a knowntechnique (J. Am. Chem. Soc., vol 95, 3310 (1973)). The aldehyde of theformula (VIII) used here, is a novel compound. There is no particularrestriction as to the method for preparing this compound. However, thiscompound can be prepared by the method shown in the following flow chart(Scheme 3). ##STR10##

Compounds (I) of the present invention and their salts have stronganti-platelet inhibitory activities and anti-anginal activities, and yettheir toxicity is weak. Therefore, they are useful for prevention andtreatment of e.g. thrombosis, angina pectoris, cardiac infarction, orarterial sclerosis.

Pharmacological test results of the compounds of the present inventionare as follows.

Inhibitory activities on platelet aggregation

From a guinea pig (Hartley strain), citric acid-added blood was obtainedby a cardiac puncture. The blood was centrifuged at 120×g for 10minutes, and the supernatant platelet rich plasma was separated.Measurement of platelet aggregation was conducted by means of anaggregometer in accordance with the Bone's nephelometry (G. V. R. Bone;Nature, vol 194, p 927, 1962). In a test in vitro, a test compound wasadded to the platelet rich plasma, and the mixture was incubated for 10minutes. Then, adensoine diphosphate (1 micro M) was added to induceplatelet aggregation. The degree of aggregation was represented by themaximum change in the light transmittance (the maximum aggregation rate)within 5 minutes after the addition of adenosine diphosphate, and theresults are shown by a 50% inhibitory concentration. In a test ex vivo,a test compound was dissolved in ethanol, then suspended in a 0.5%tragacanth solution or in a 1% β-cyclodextrin solution and orallyadministered. From blood obtained by a cardiac puncture 30 minutes afterthe administration, a platelet rich plasma was prepared, and plateletaggregation was measured in the same manner as in the case of the testin vitro. The results are shown in Table 1.

In Table 1 and subsequent Tables, the following abbreviations are usedto represent compounds and solvents. Further, as a reference compound,the compound F (natural prostagrandin I₂) was used.

Compound A: sodium salt of 2,3-methylene-7α-fluoro-17,20-dimethylPGI₂prepared in Example 1

Compound B-b: high polarity isomer of methyl ester of(1S*,3S*)-2,4-ethylene-7α-fluoro-17,20-dimethylPGI₂ prepared in Example3

Compound C: methyl ester of(1S*,3R*)-2,4-ethylene-7α-flouro-17,20-dimethylPGI₂ prepared in Example4

Compound D-a: low polarity isomer of methyl ester of2,4-methylene-7α-fluoro-17,20-dimethylPGI₂ prepared in Example 7

Compound D-b: high polarity isomer of methyl ester of2,4-methylene-7α-fluoro-17,20-dimethylPGI₂ prepared in Example 7

Compound E-a: low polarity isomer of sodium salt of2,4-methylene-7α-fluoro-17,20-dimethylPGI₂ prepared in Example 7

Compound E-b: high polarity isomer of sodium salt of2,4-methylene-7α-fluoro-17,20-dimethylPGI₂ prepared in Example 7

Compound F: natural PGI₂

Solvent X: 0.5% tragacanth solution

Solvent Y: 1% β-cyclodextrin solution

                  TABLE 1                                                         ______________________________________                                                in vitro   ex vivo                                                    Compound  IC.sub.50 (ng/ml)                                                                          MED (mg/kg) Solvent                                    ______________________________________                                        Compound A                                                                              18.3         --          X                                          Compound B-b                                                                            0.87         0.3         X                                          Compound C                                                                              5.50         --          X                                          Compound D-a                                                                            2.88         0.3         Y                                          Compound D-b                                                                            1.50         0.3         Y                                          Compound E-a                                                                            1.13         --          Y                                          Compound E-b                                                                            1.70         0.3         Y                                          Compound F                                                                              --           >10         Y                                          ______________________________________                                         MED: Minimum effective dose showing significant inhibitory effects (P <       0.05)                                                                    

As is apparent from the above Table, compounds of the present inventionhave strong anti-platelet activities.

Anti-anginal activities (Preventive activities on vasopressin-induced STdepression)

Vasopressin (0.2 IU/kg) was administered from the femoral vein of a malerat (Donryou strain) anesthetized with pentobarbital, and theelectrocardiogram was recorded for 5 seconds each at intervals of 30seconds over a period of 5 minutes after the administration. Thedepression of ST-segment (the average of five pulses) was calculated onthe electrocardiogram. The test compound was dissolved in ethanol andintravenously administered 2 minutes prior to the administration ofvasopressin, or after being dissolved in ethanol, suspended in a 0.5%tragacanth solution or in a 1% β-cyclodextrin solution and orallyadministered 30 minutes prior to the administration of vasopressin. Thedifferences of the ST depression between the test compound-administeredgroup and the non-treated control group (5 animals for each group) wereanalysed by two-way layout analysis of variance. The results are shownin Table 2.

                  TABLE 2                                                         ______________________________________                                                Intravenous                                                                   administration                                                                           Oral administration                                        Compound  MED (μ/kg)                                                                              MED (mg/kg) Solvent                                    ______________________________________                                        Compound B-b                                                                            1.0           0.01       X                                          Compound D-b                                                                            --           0.1         Y                                          Compound E-a                                                                            1.0          0.1         Y                                          Compound E-B                                                                            1.0          0.1         Y                                          ______________________________________                                         MED: Minimum effective dose showing a significant preventive activity (P      0.05)                                                                    

As shown in the above Table, compounds of the present invention havestrong anti-anginal activities.

Acute toxicity

To male mice of ddY strain weighing 25-32 g (five animals per eachgroup), a predetermined dose of a test compound dissolved in a smallamount of ethanol and then diluted with a 1% β-cyclodextrin solution,was orally administered, and the mortality was recorded over a period of7 days after the administration. The results are shown in Table 3.

                  TABLE 3                                                         ______________________________________                                                     Dose     Number of dead animals/                                 Compound     (mg/kg)  Number of test animals                                  ______________________________________                                        Compound D-b 20       0/5                                                     Compound E-b 20       0/5                                                     ______________________________________                                    

As shown in Table 3, the toxicity of the compounds of the presentinvention is very low.

The compound of the present invention may be administered orally orparenterally such as subcutaneously, intramuscularly, intravenously,percutaneously or intrarectally. Compositions for oral administrationmay be solid compositions such as tablets, granules, powders orcapsules, or liquid compositions such as emulsions, solutions,suspensions, syrups or elixirs. The tablets may be formed by a usualmethod employing an excipent such as lactose, starch, crystallinecellulose or polyvinyl pyrrolidone; a binder such as carboxymethylcellulose or methyl cellulose; and a disintegrator such as sodiumalginate, sodium hydrogen carbonate or sodium lauryl sulfate. Thegranules and powders can likewise be formed by usual methods by means ofe.g. the above excipients. Capsules can be prepared, for example, byfilling a solution obtained by dissolving the compounds of the presentinvention in a vegetable oil such as coconut oil, into gelatin softcapsules.

Compositions for non-oral administration may be sterile aqueous ornon-aqueous solutions, suspensions or emulsions, or sterile solidcompositions to be dissolved in sterile injectable medium immediatelybefore use. Further, a suppository for intrarectal administration or apessary for administration in vagina may be administered.

The compound of the present invention may be used for formulation in theform of a clathrate compound with α-, β- or γ-cyclodextrin, ormethylated cyclodextrin.

A daily dose of the compound of the present invention is usually from0.0001 to 1.0 mg/kg. It is preferably from 0.0001 to 0.3 mg/kg in thecase of intramuscular, subcutaneous or intravenous administration andfrom 0.0001 to 1.0 mg/kg in the case of oral administration. However,the dose varies depending upon the age and weight of the patient, thedegree of disease, the type of disease and the number ofadministrations, and it is not restricted to the above ranges.

Now, the present invention will be described in further detail withreference to Reference Examples, Working Examples and PreparativeExamples. However, it should be understood that the present invention isby no means restricted to such specific Examples.

REFERENCE EXAMPLE 1 Preparation of 2-bromomethylcyclopropanecarboxylicacid ethyl ester

(2-formyl)cyclopropanecarboxylic acid ethyl ester (14.2 g, 0.10 mol) wasdissolved in methanol (200 ml). The solution was cooled to 0° C., andsodium borohydride (3.8 g, 0.10 mol) was added. The mixture was stirredfor 20 minutes. After distilling off the solvent, a saturated sodiumchloride aqueous solution was added thereto. The product was extractedwith chloroform, then dried and concentrated. Then, it was purified bysilica gel column chromatography (hexane:ethyl acetate=2:1) to obtain(2-hydroxymethyl)cyclopropanecarboxylic acid ethyl ester (14.3 g, yield:99%).

The (2-hydroxymethyl)cyclopropanecarboxylic acid ethyl ester (14.3 g,0.1 mol) was dissolved in N,N-dimethylformamide (150 ml), andtriphenylphosphine (25.9 g, 0.1 mol) was added thereto at roomtemperature. The mixture was stirred for 10 minutes. After cooling themixture to 20° C., bromine (15.8 g, 0.1 mol) was dropwise added theretoover a period of 10 minutes. One hour later, the reaction mixture wasadded to a saturated sodium hydrogen carbonate solution, and the productwas extracted with ethyl ether. It was dried, concentrated and thenpurified by column chromatography (hexane:ethyl acetate=5:1) to obtain(2-bromomethyl)cyclopropane carboxylic acid ethyl ester (15.3 g, yield:74%).

¹ NMR(CDCl₃) δ0.9-1.0(m, 1H), 1.27(t, J=7.6 Hz, 3H), 1.3-1.5(m, 1H),1.6-1.7(m, 1H, 1.8-2.0(m, 1H), 3.3-3.4(m, 2H), 4.25(q, J=7.6 Hz, 2H)

REFERENCE EXAMPLE 2 Preparation of 2-bromomethylcyclopropylmethanol

The (2-bromomethyl)cyclopropanecarboxylic acid ethyl ester (15.3 g, 74mmol) was dissolved in ethyl ether (50 ml) and then added to asuspension of lithium aluminum hydride (2.8 g, 74 mmol) in ethyl ether(150 ml). The mixture was stirred at room temperature for one hour.Then, 2N hydrochloric acid was added thereto, and the product wasextracted with ethyl ether, dried and concentrated. It was then purifiedby column chromatography to obtain (2-bromomethyl)cyclopropylmethanol(6.7 g, yield: 55%).

¹ H-NMR (CDCl₃) δ0.6-0.7(m, 1H), 07.-0.8(m, 1H), 1.0-1.2(m, 2H),1.7-1.8(m, 1H), 3.2-3.6(m, 4H)

REFERENCE EXAMPLE 3 Preparation of 2-bromomethylcyclopropylmethylt-butyldimethylsilyl ether

The (2-bromomethyl)cyclopropylmethanol (6.7 g, 41 mmol) was dissolved inN,N-dimethylformamide (80 ml), and imidazole (6.8 g, 0.1 mol) andt-butyldimethylsilyl chloride (9.0 g, 60 mmol) was added thereto at 0°C. The mixture was stirred for one hour. Then, water was added thereto,and the product was extracted with ethyl ether, then dried andconcentrated. Then, it was purified by silica gel column chromatographyto obtain (2-bromomethyl)cyclopropylmethyl t-butyldimethylsilyl ether(10.5 g, yield: 92%).

¹ N-NMR(CDCl₃) δ0.08(s, 6H), 0.5-0.6(m, 1H), 0.7-0.8(m, 1H), 0.92(s,9H), 1.0-1.1(m, 1H), 1.2-1.3(m, 1H), 3.3-3.4(m, 2H), 3.56(d, J=5.6 Hz,2H)

REFERENCE EXAMPLE 4 Preparation of2-(4-tetrahydropyranyloxy-2-butynyl)cyclopropylmethylt-butyldimethylsilyl ether

Propargyl alcohol tetrahydropyranyl ether (5.6 g, 40 mmol) was dissolvedin tetrahydrofuran (80 ml), and the solution was cooled to -78° C.Butyllithium (27 ml, factor=1.48, 40 ml) was added thereto. Fifteenminutes later, the temperature was raised to 0° C. Ten minutes later,hexamethylphosphoric triamide (14.3 g, 80 mmol) was added thereto, and atetrahydrofuran solution (20 ml) of (2-bromomethyl)cyclopropylmethylt-butyldimethylsilyl ether (11.2 g, 40 mmol) was added thereto. Themixture was stirred at 0° C. for one hour and at room temperature for 3hours. Water was added thereto, and the product was extracted with ethylether, then dried and concentrated. Then, it was purified by silica gelcolumn chromatography to obtain2-(4-tetrahydropyranyloxy-2-butynyl)cyclopropylmethylt-butyldimethylsilyl ether (5.8 g, yield: 43%).

¹ N-NMR(CDCl₃) δ0.00(s, 6H), 0.4-0.5(m, 1H), 0.8-1.0(m, 3H), 0.86(s,9H), 1.4-1.9(m, 6H), 2.2-2.3(m, 2H), 3.4-3.5(m, 3H, 3.8-3.9(m, 1H),4.15(d, J=14 Hz, 1H), 4.23(d, J=14 Hz), 1H), 4.7-4.8(m, 1H)

REFERENCE EXAMPLE 5 Preparation of2-(4-hydroxy-2-butynyl)cyclopropanecarboxylic acid methyl ester

The 2-(4-tetrahydropyranyloxy-2-butynyl)cyclopropylmethylt-butyldimethylsilyl ether (5.8 g, 17.2 mmol) was dissolved intetrahydrofuran (50 ml), and a tetrabutyl ammonium fluoride (factor=1.0)tetrahydrofuran solution (33 ml, 33 mmol) was added thereto at 0° C. Themixture was stirred for one hour. The product was purified by columnchromatography to obtain2-(4-tetrahydropyranyloxy-2-butynyl)cyclopropylmethanol (4.3 g).

The 2-(4-tetrahydropyranyloxy-2-butynyl)cyclopropylmethanol (4.3 g) wasdissolved in acetone (30 ml) and then oxidized to acyclopropanecarboxylic acid with a John's reagent at 0° C.

The crude product was dissolved in ethyl ether (50 ml) andmethyl-esterified with diazomethane. The reaction solution wasconcentrated, and the crude product was dissolved in ethanol (30 ml).Then, pyridinium p-toluenesulfonate (0.5 g) was added thereto, and themixture was heated to 50° C. and stirred for 1.5 hours. Then, asaturated sodium hydrogen carbonate solution was added thereto, and theproduct was extracted with dichloromethane. It was dried over anhydrousmagnesium salfate, concentrated and then purified by silica gel columnchromatography to obtain 2-(4-hydroxy-2-butynyl)cyclopropane carboxylicacid methyl ester (0.7 g).

¹ N-NMR(CDCl₃) δ0.9-1.0(m, 1H), 1.1-1.3(m, 1H), 1.5-1.7(m, 1H),1.8-1.9(m, 1H), 2.4-2.5(m, 2H), 3.64(s, 3H), 4.22(s, 2H)

REFERENCE EXAMPLE 6 Preparation of2-(4-oxo-2-butynyl)cyclopropanecarboxylic acid methyl ester

Oxalyl chloride (0.78 g, 6.2 mmol) was dissolved in dichloromethane (12ml), and the solution was cooled to -40° C. A solution ofdimethylsufloxide (1.0 g, 12.3 mmol) in dichloromethane (4 ml) wasdropwise added thereto over a period of 10 minutes. Fifteen minuteslater, a solution of 2-(4-hydroxy-2-butynyl)cyclopropanecarboxylic acidmethyl ester (0.70 g, 4.1 mmol) in dichloromethane (5 ml) was dropwiseadded thereto over a period of 15 minutes. Forty minutes later,triethylamine (2.5 g, 25 mmol) was added thereto, and the temperaturewas raised to 0° C. Water was added thereto, and the product wasextracted with dichloromethane, and the crude product thereby obtainedwas roughly separated by silica gel column chromatography to obtain2-(4-oxo-2-butynyl)cyclopropanecarboxylic acid methyl ester (0.32 g).

REFERENCE EXAMPLE 7 Preparation of 2-(2-hydroxyethyl)cyclopropylmethylt-butyldimethylsilyl ether

2-vinylcyclopropylmethyl t-butyldimethylsilyl ether (17.1 g, 81 mmol)was dissolved in tetrahydrofuran (100 ml) and cooled to 0° C. Aborane-dimethylsulfide complex (2.5 g, 33 mmol) was added thereto, andthe mixture was stirred for one hour. Ethanol (38 ml), 3N sodiumhydroxide (38 ml) and 30% hydrogen peroxide (18.2 ml) were addedthereto, and the mixture was stirred for 30 minutes. The saturatedsodium chloride aqueous solution was added thereto, and the product wasextracted with ethyl acetate, then dried over anhydrous magnesiumsulfate and concentrated. Then, it was purified by silica gel columnchromatography to obtain 2-(2-hydroxyethyl)cyclopropylmethylt-butyldimethylsilyl ether (15.0 g, yield: 81%).

¹ N-NMR(CDCl₃) δ0.00(s, 3H), 0.05(s, 3H), 0.3-0.4(m, 2H), 0.5-0.6(m,1H), 0.91(s, 9H), 0.9-1.0(m, 1H), 1.1-1.2(m, 1H), 1.81(dq, J=14.0, 4.7Hz, 1H), 3.03(dt, J=9.4, 10.3 Hz, 1H), 3.71(d, J=4.2 Hz, 1H), 3.75(d,J=4.2 Hz, 1H), 3.94(dd, J=10.3, 5.1 Hz, 1H)

REFERENCE EXAMPLE 8 Preparation of2-(5-tetrahydropyranyloxy-3-pentynyl)cyclopropylmethylt-butyldimethylsilyl ether

2-(2-hydroxyethyl)cyclopropylmethyl t-butyldimethylsilyl ether (15.0 g,65 mmol) was dissolved in N,N-dimethylformamide (120 ml), andtriphenylphosphine (17.3 g, 66 mmol) was added thereto at roomtemperature. Twenty minutes later, the mixture was cooled to -20° C.Bromine (10.5 g, 66 mmol) was added thereto over a period of 5 minutes,and the temperature was gradually raised to 0° C. The mixture was pouredinto a saturated sodium hydrogen carbonate aqueous solution, and theproduct was extracted with ethyl ether. Then, it was dried overanhydrous magnesium sulfate and purified by silica gel columnchromatography to obtain 2-(2-bromoethyl)cyclopropylmethylt-butyldimethylsilyl ether (2.7 g).

A tetrahydrofuran solution (15 ml) of propargyl alcoholtetrahydropyranyl ether (1.44 g, 10.3 mmol) was cooled to -78° C., andbutyllithium (factor=1.5, 6.9 ml, 10.3 mmol) was added thereto. Fifteenminutes later, the temperature was raised to 0° C. Hexamethylphosphorictriamide (3.76 ml, 21 mmol) was added thereto, and the mixture wasstirred for 15 minutes. A tetrahydrofuran solution of2-(2-bromoethyl)cyclopropylmethyl t-butyldimethyl silyl ether (2.73 g,10.3 mmol) was added thereto, and the mixture was stirred at roomtemperature for 2 hours. A saturated ammonium chloride solution wasadded thereto, and the product was extracted with ethyl ether. The crudeproduct was purified by silica gel column chromatography to obtain2-(5-tetrahydropyranyloxy-3-pentynyl)cyclopropylmethylt-butyldimethylsilyl ether (3 g).

¹ N-NMR(CDCl₃) δ0.00(s, 6H), 0.2-0.3(m, 1H), 0.3-0.4(m, 1H), 0.6-0.7(m,1H), 0.7-0.8(m, 1H), 0.87(s, 9H), 1.4-1.9(m, 8H), 2.2-2.3(m, 2H),3.4-3.5(m, 3H), 3.7-3.9(m, 1H), 4.14(d, J=14.0 Hz, 1H), 4.26(d, J=14.0Hz, 1H), 5.76(t, J=3.7 Hz, 1H).

REFERENCE EXAMPLE 9 Preparation of2-(5-tetrahydropyranyloxy-3-pentynyl)cyclopropylmethanol

The 2-(5-tetrahydropyranyloxy-3-pentyl)cyclopropylmethylt-butyldimethylsilyl ether (3 g, 10 mmol) was dissolved intetrahydrofuran (10 ml), and tetrabutyl ammonium fluoride (factor=1.0,12 ml, 12 mmol) was added at 0° C. The mixture was stirred for 30minutes. The solvent was distilled off, and the product was purified bysilica gel column chromatography to obtain2-(5-tetrahydropyranyloxy-3-pentynyl)cyclopropanemethanol (1.2 g)

¹ N-NMR(CDCl₃) δ0.2-0.4(m, 2H), 0.6-0.8(m, 1H), 0.88(t, J=7.5 Hz, 1H),1.1-1.9(m, 8H), 2.2-2.4(m, 2H), 3.3-3.6(m, 3H), 3.7-3.9(m, 1H), 4.14(d,J=15 Hz, 1H), 4.27(d, J=15 Hz, 1H), 4.76(s, 1H)

REFERENCE EXAMPLE 10 Preparation of2-(5-hydroxy-3-pentynyl)cyclopropanecarboxylic acid methyl ester

The alcohol (0.70 g, 2.9 mmol) prepared in Reference Example 9 wasdissolved in dichloromethane (30 ml), and pyridinium chlorochromate(0.90 g) was added thereto. The mixture was stirred at room temperaturefor 6 hours. The reaction mixture was filtered through Celite andconcentrated to obtain an aldehyde (0.62 g).

To the above aldehyde (0.62 g), a mixture comprising a solution ofsilver nitrate (2 g) in water (4 ml) and a solution of sodium hydroxide(0.93 g) in water (4 ml), was added at 0° C., and the mixture wasstirred for 5 minutes. The mixture was filtered through Celite andadjusted to pH7 with concentrated hydrochloric acid. The solvent wasdistilled off, and the residue was dissolved in ethyl ether (3 ml) andmethyl-esterified by an addition of diazomethane-ethyl ether solution.The product was purified by silica gel column chromatography to obtain amethyl ester compound (0.46 g).

The above methyl ester compound (0.45 g, 1.5 mmol) was dissolved inethanol (30 ml), and pyridinium p-toluenesulfonate (80 mg, 0.3 mmol) wasadded thereto. The mixture was stirred at 60° C. for 2 hours. Theproduct was purified by silica gel column chromatography to obtain theabove identified compound (0.31 g).

¹ N-NMR(CDCl₃) δ0.8-2.0(m, 6H), 2.3-2.5(m, 3H), 3.68(s, 3H), 4.25(s, 2H)

REFERENCE EXAMPLE 11 Preparation of2-(5-oxo-3-pentynyl)cyclopropanecarboxylic acid methyl ester

Oxalyl chloride (0.40 g, 3.1 mmol) was dissolved in dichloromethane, andthe solution was cooled to -40° C. A solution of dimethyl sulfoxide(0.52 g, 6.2 mmol) in dichloromethane (2 ml) was added thereto over aperiod of 5 minutes, and the mixture was stirred for 20 minutes. Asolution of 2-(5-hydroxy-3-pentynyl)cyclopropanecarboxylic acid methylester (0.37 g, 2 mmol) in dichloromethane (5 ml) was added thereto, andthe mixture was stirred for 30 minutes. Then, triethylamine (1.7 ml, 12mmol) was added thereto. The temperature was raised to 0° C., and asaturated sodium chloride aqueous solution was added thereto. Theproduct was extracted with dichloromethane, dried over anhydrousmagnesium sulfate and then purified by silica gel column chromatographyto obtain the above identified compound (0.35 g, yield: 96%).

REFERENCE EXAMPLE 12 Preparation of(1S*,3S*)-3-(3-(tetrahydropyranyloxy-1-propynyl)cyclopentanecarboxylicacid methyl ester

To a solution of a borane-dimethylsulfide complex (1.98 ml, 20.2 mmol)in THF (18.3 ml), a 1M THF solution of 2,3-dimethyl-2-butene (20.2 ml,20.2 mmol) was added at 0° C., and the mixture was stirred at the sametemperature. Two hours later, the reaction solution was cooled to -25°C., and a solution of 3-cyclopentenecarboxylic acid methyl ester (2.55g, 20.2 mmol) in THF (20 ml) was dropwise added thereto. The mixture wasstirred at the same temperature for 1.5 hours. Then, methanol (1.64 ml)was dropwise added thereto. The reaction temperature was raised to 0°C., and the mixture was stirred for one hour. The reaction solution wasconcentrated under reduced pressure, dried and then dissolved in THF (20ml). Separately, a n-butyllithium/1.5M hexane solution (1.37 ml, 20.6mmol) was added at 0° C. to a solution of propargyl tetrahydropyranylether (2.83 g, 20.2 mmol) in THF (20 l), and the mixture was stirred forone hour. This solution was dropwise added at 0° C. to the above THFsolution (10 ml). Then, the reaction solution was cooled to -78° C., anda solution of iodine (5.13 g, 20.2 mmol) in THF (10 ml) was dropwiseadded thereto, and the mixture was stirred at the same temperature forone hour and at room temperature for two hours. A 2N sodium hydroxideaqueous solution (12.1 ml) and a 30% hydrogen peroxide aqueous solution(2.83 ml) were dropwise added thereto, and the mixture was stirred for 5minutes, then diluted with ethyl acetate (150 ml) and washed with asaturated sodium thiosulfate aqueous solution (150 ml) and a saturatedsodium chloride aqueous solution (150 ml). The organic layer was driedover anhydrous magnesium sulfate and then concentrated under reducedpressure. The residue was purified by silica gel column chromatographyto obtain the above identified compound (2.56 g, 47.6%).

¹ N-NMR(CDCl₃) δ1.50-2.10(m, 12H), 2.80-3.01(m, 2H), 3,48-3.60(m, 1H),3.67(s, 3H), 3.80-3.92(m, 1H), 4.18(d, J=15 Hz, 1H), 4.30(d, J=15 Hz,1H), 4.70-4.80(m, 1H)

REFERENCE EXAMPLE 13 Preparation of(1S*,3S*)-3-(3-hydroxy-1-propynyl)cyclopentanecarboxylic acid methylester

The carboxylic acid methyl ester (1.0 g, 3.75 mol) prepared in ReferenceExample 12 was dissolved in methanol (4 ml), and pyridiniump-toluenesulfonate (PPTS (100 mg, 0.4 mmol)) was added thereto. Themixture was stirred at 50° C. for one hour and 30 minutes. The reactionsolution was concentrated under reduced pressure and purified by silicagel column chromatography to obtain the above identified compound (532mg, 78.0%).

¹ N-NMR(CDCl₃) δ1.60-2.10(m, 6H), 2.80-3.02(m, 2H), 3.68(s, 3H), 4.24(s,2H)

REFERENCE EXAMPLE 14 Preparation of(1S*,3S*)-3-(3-oxo-1-propynyl)cyclopentanecarboxylic acid methyl ester

Using the compound (1.95 g, 10.7 mmol) prepared in Reference Example 13,the above identified compound (1.31 g, yield: 67.7%) was prepared in thesame manner as in Reference Example 6.

¹ N-NMR(CDCl₃) δ1.80-2.35(m, 6H), 2.95-3.10(m, 2H), 3.69(s, 3H), 9.19(s,1H)

REFERENCE EXAMPLE 15 Preparation of(1S*,3R*)-3-(3-tetrahydropyranyloxy-1-propynyl)cyclopentanecarboxylicacid methyl ester

To a solution of diisopropylamine (16.6 ml, 118.4 mmol) in THF (250 ml),a 1.5M hexane solution of N-butyllithium (71.0 ml, 1.6.6 mmol) was addedat 0° C., and the mixture was stirred for 15 minutes. The reactionsolution was cooled to -70° C., and then a solution of the compound(15.8 g, 59.2 mmol) prepared in Reference Example 12, in THF (960 ml),was dropwise added thereto. The mixture was stirred at the sametemperature for 20 minutes. The reaction solution was poured into asaturated ammonium chloride aqueous solution (300 ml) and extracted withethyl ether (150 ml×2). The organic layer was dried over anhydrousmagnesium sulfate, and then the solvent was distilled off under reducedpressure. The residue was purified by silica gel column chromatography(hexane:ethyl acetate=20:1 to 4:1) to obtain the above identifiedcompound (2.34 g, 8.76 mmol, yield: 14.8%) and recovered startingmaterial (8.53 g, yield: 54.0%).

¹ N-NMR(CDCl₃) δ1.50-2.38(m, 12H), 2.60-2.84(m, 2H), 3,48, 3.60(m, 1H),3.68(s, 3H), 3.80- 3.92(m, 1H), 4.19(d, J=15 Hz, 1H), 4.30(d, J=15 Hz,1H), 4.75-4.85(m, 1H)

REFERENCE EXAMPLE 16 Preparation of(1S*,3R*)-3-(3-hydroxy-1-propynyl)cyclopentanecarboxylic acid ester

Using the compound (2.34 g, 8.76 mmol) prepared in Reference Example 15,the above identified compound (1.41 g, 7.75 mmol, yield: 88.5%) wasobtained in the same manner as in Reference Example 13.

¹ N-NMR(CDCl₃) δ1.72-2.35(m, 6H), 2.62-2.90(m, 2H), 3.69(s, 3H), 4.25(s,2H)

REFERENCE EXAMPLE 17 Preparation of(1S*,3R*)-3-(3-oxo-1-propynyl)cyclopentanecarboxylic acid methyl ester

Using the compound (1.40 g, 7.75 mmol) prepared in Reference Example 16,the above identified compound (1.08 g, 6.05 mmol, yield: 77.4%) wasobtained in the same manner as in Reference Example 6.

¹ N-NMR(CDCl₃) δ1.80-2.42(m, 6H), 2.75-2.95(m, 2H), 3.70(s, 3H), 9.19(s,1H)

REFERENCE EXAMPLE 18 Preparation of4-(t-butyldimethylsiloxymethyl)-1-cyclohexanecarboaldehyde

1,4-cyclohexanedimethanol (72.1 g) was dissolved inN,N-dimethylformamide (500 ml), and imidazole (68.1 g) andt-butyldimethylsilyl chloride (65.4 g) were added thereto. The mixturewas stirred at room temperature for 14 hours. It was poured into asaturated sodium bicarbonate aqueous solution, then extracted with ethylether and dried. It was purified by silica gel column chromatography toobtain a monosilyl ether (72.5 g).

Then, a solution of dimethylsulfoxide (30.1 ml) in methylene chloride(95 ml) was added at -78° C. to a solution of oxalyl chloride (18.5 ml)in methylene chloride (480 ml). The mixture was stirred for 5 minutes,and then above-mentioned solution of the monosilyl ether (50 g) inmethylene chloride (190 ml) was added thereto at -78° C. The mixture wasstirred for further 30 minutes. Triethylamine (135 ml) was dropwiseadded thereto at -78° C., then the temperature was gradually raised toroom temperature. The reaction mixture was poured into water (1 l), andthe aqueous layer was extracted with methylene chloride. The extractsolutions were put together and washed with an aqueous sodium chloridesolution, then dried, concentrated and thereafter purified by columnchromatography to obtain the above identified compound (49 g).

¹ N-NMR(CDCl₃) δ0.84-0.85(m, 9H), 3.37(m, 2H), 9.58(s, 1H)

REFERENCE EXAMPLE 19 Preparation of4-(2,2-dibromovinyl)-1-cyclohexanemethanol t-butyldimethylsilyl ether

To a solution of the above-mentioned aldehyde (57.6 g) in methylenechloride (600 ml), solution of triphenylphosphine (118 g) and carbontetrabromide (81.9 g) in methylene chloride (200 ml) was added at 0° C.The mixture was stirred for one hour and then poured into a saturatedsodium bicarbonate aqueous solution. The product was extracted withethyl ether. The extract solution was washed with an aqueous sodiumchloride solution, then dried and purified by column chromatography toobtain the above identified compound (67.6 g).

¹ N-NMR(CDCl₃) δ0.86(s, 9H), 3.4(m, 2H)

REFERENCE EXAMPLE 20 Preparation of4-(-3-tetrahydropyranyloxy-1-propynyl)cyclohexanemethanolt-butyldimethylsilyl ether

To a solution of the above dibromide (62 g) in tetrahydrofuran (500 ml),n-butyllithium (a 1.5M hexane solution, 207 ml) was added, and themixture was cooled to -78° C. Then, paraformamide (9.34 g) was addedthereto, and the mixture stirred at -20° C. for 12 hours and at roomtemperature for 2 hours. Then, the mixture was poured into a saturatedsodium bicarbonate aqueous solution and extracted with ethyl ether. Theextract solution was washed with an aqueous sodium chloride solution,then dried and concentrated. The residue was dissolved in methylenechloride (310 ml), and 2,3-dihydropyrane (15.7 ml) and p-toluenesulfonicacid (2.97 g) were added thereto. The mixture was stirred at roomtemperature for 14 hours. It was then poured into a saturated sodiumbicarbonate aqueous solution, then extracted with methylene chloride,dried and concentrated. Then, it was purified by column chromatographyto obtain the above identified compound (31.6 g).

¹ N-NMR(CDCl₃) δ0.86(s, 9H), 3.37(m, 2H), 4,79(m, 1H)

REFERENCE EXAMPLE 21 Preparation of4-(3-tetrahydropyranyloxy-1-propynyl)-1-cyclohexanemethanol

To a solution of the above silyl ether (31.6 g) in tetrahydrofuran (170ml), tetrabutyl ammonium fluoride (1M, a tetrahydrofuran solution, 94.8ml) was added at 0° C., and the mixture was stirred at room temperaturefor 14 hours, then concentrated and purified by column chromatography toobtain the above identified compound (21.3 g).

¹ N-NMR(CDCl₃) δ4.18(m, 1H)

REFERENCE EXAMPLE 22 Preparation of4-(3-tetrahydropyranyloxy-1-propynyl)-1-cyclohexanecarbaldehyde

To a solution of oxalyl chloride (6.38 ml) in methylene chloride (165ml), a solution of dimethylsulfoxide (10.38 ml) in methylene chloride(35 ml) was dropwise added at -78° C. The mixture was stirred for 10minutes, and then a solution of the above alcohol (16.78 g) in methylenechloride (655 ml) was dropwise added thereto at -78° C., and the mixturewas stirred for 30 minutes. Triethylamine (46.3 ml) was dropwise addedthereto at -78° C., and the temperature was gradually raised to roomtemperature. The mixture was stirred at room temperature for 30 minutesand then poured into water and extracted with methylene chloride. Theextract solution was washed with an aqueous sodium chloride solution,then dried, concentrated and purified by column chromatography to obtainthe above identified compound (16.0 g).

¹ N-NMR(CDCl₃) δ4.80(m, 1H), 9.63(m, 1H)

REFERENCE EXAMPLE 23 Preparation of4-(3-hydroxy-1-propynyl)-1-cyclohexanecarboxylic acid methyl ester

The above aldehyde (16.0 g) was added at 0° C. to a mixture comprisingan aqueous solution (45 ml) of silver nitrate (22.7 g) and an aqueoussolution (45 ml) of sodium hydroxide, and the mixture was stirred at 0°C. for 15 minutes. The reaction mixture was filtered through Celite,washed with hot water and then left to cool. The reaction mixture wasacidified with hydrochloric acid and then extracted with ethyl ether.The extract solution was dried and concentrated. The residue wasdissolved in ethyl ether (120 ml), and diazomethane (0.5M, an ethylether solution, 13 ml) was dropwise added thereto at 0° C. The reactionsolution was concentrated, and the residue was dissolved in ethanol (100ml). Pyridinium p-toluenesulfonate (0.89 g) was added thereto, and themixture was stirred at 40° C. for 30 minutes and at 55° C. for 3.5hours. The mixture was poured into a saturated sodium bicarbonateaqueous solution, then extracted with chloroform, dried andconcentrated. Then, it was purified by column chromatography to obtainthe above identified compound (7.42 g).

¹ N-NMR(CDCl₃) δ1.3-2.4(m, 10H), 3.67(m, 3H), 4.25(m, 2H) IR(CDCl₃)3600, 3460, 2210, 1720 cm⁻¹

REFERENCE EXAMPLE 24 Preparation of4-(3-oxo-1-propynyl)cyclohexanecarboxylic acid methyl ester

A solution of dimethylsulfoxide (5.91 ml) in methylene chloride (19 ml)was added at -78° C. to a solution of oxalyl chloride (3.63 ml) inmethylene chloride (95 ml), and the mixture was stirred for 5 minutes.Then, a solution of an alcohol (7.02 g) in methylene chloride (38 ml)was dropwise added thereto at -78° C., and the mixture was stirred for30 minutes. Then, triethylamine (26.4 ml) was added at -78° C., and thetemperature was raised to room temperature. Then, the mixture wasstirred for 30 minutes. Then, it was poured into water and extractedwith methylene chloride. The extract solution was washed with an aqueoussodium chloride solution, dried and concentrated. Then, it was purifiedby column chromatography to obtain the above identified methyl ester(5.2 g).

¹ N-NMR(CDCl₃) δ1.4-2.5(m, 10H), 3.68(m, 3H), 9.19(m, 1H)

EXAMPLE 1 Sodium salt of 2,3-methylene-7α-fluoro-17,20-dimethylPGI₂Example 1-1 Preparation of5,6-dehydro-2,3-methylene-7-hydroxy-17,20-dimethylPGE₂ methyl ester11,15-bis(t-butyldimethyl)silyl ether

t-Butyllithium (factor=1.5, a pentane solution, 2.7 ml, 4.0 mmol) wasadded to ethyl ether (5 ml) at -78° C.(1E,3S,5S)-3-t-butyldimethylsiloxy-5-methyl-1-iodo-1-nonene (0.79 g, 2.0mmol) was dissolved in ethyl ether (5 ml) and dropwise added theretoover a period of 10 minutes. The mixture was stirred for 2 hours at -78°C. Then, pentyl copper (0.26 g, 2.0 mmol) and HMPT (0.65 g, 4.0 mmol)were dissolved in ethyl ether (10 ml) and dropwise added thereto over aperiod of 15 minutes. One hour and thirty minutes later,(4R)-4-t-butyldimethylsiloxy-2-cyclopentenone (0.40 g, 1.9 mmol) wasdissolved in ethyl ether (10 ml) and added thereto. Twenty minuteslater, the temperature was raised to -40° C. Further,2-(4-oxo-2-butynyl)cyclopropanecarboxylic acid methyl ether (0.32 g, 2.0mmol) was dissolved in ethyl ether (10 ml) and dropwise added theretoover a period of 15 minutes. The mixture was stirred for one hour at-40° C., and then a saturated ammonium chloride aqueous solution wasadded thereto, and the product was extracted with ethyl ether. Theextract was purified by silica gel chromatography to obtain the aboveidentified compound (0.66 g, yield: 53%).

¹ N-NMR(CDCl₃) δ-0.1-0.1(m, 12H), 0.6-1.0(m, 27H), 1.0-1.5(m, 9H),2.2-2.9(m, 9H), 3.65(s, 3H), 4.0-4.2(m, 2H), 5.5-5.7(m, 2H)

Example 1-2 Preparation of5,6-dehydro-2,3-methylene-7-trimethylsiloxy-17,20-dimethylPGF₂ α methylester 11,15-bis(t-butyldimethyl)silyl-9-triethylsilyl ether

The alcohol (0.40 g, 0.62 mmol) prepared in Example 1-1 was dissolved indichloromethane (5 ml), and the solution was cooled to 0° C. Pyridine(0.50 ml, 6.2 mmol) and chlorotrimethylsilane (0.20 ml, 1.55 mmol) wereadded thereto, and post-treatment was conducted. The crude product wasdissolved in methanol (6 ml), and the solution was cooled to -30° C.Then, sodium borohydride (78 mg, 2.1 mmol) was added thereto, and themixture was stirred for 40 minutes. A saturated ammonium chlorideaqueous solution was added thereto, and post-treatment was conducted.

The crude product thereby obtained was dissolved in pyridine (5 ml), andthe solution was cooled to -12° C. Chlorotriethylsilane (0.22 ml, 1.3mmol) was added thereto, and the mixture was stirred at 0° C. for 30minutes. A saturated sodium hydrogen carbonate aqueous solution wasadded thereto, and the product was extracted with hexane, dried andconcentrated. Then, it was purified by silica gel column chromatographyto obtain the above identified compound (0.32 g).

¹ N-NMR(CDCl₃) δ-0.1-0.1(m, 12H), 0.5-0.7(m, 6H), 0.7-1.0(m, 36H),1.1-1.6(m, 9H), 1.9-2.7(m, 7H), 3.63(s, 3H), 3.8-4.2(m, 3H), 4.5-4.7(m,1H), 5.4-5.6(m, 2H)

Example 1-3 Preparation of5,6-dehydro-2,3-methylene-7β-fluoro-17,20-dimethylPGF₂ α methyl ester11,15-bis(t-butyldimethyl)silyl-9-triethylsilyl ether

The trimethylsilyl ether (0.32 g, 0.39 mmol) prepared in Example 1-2 wasdissolved in 1,1,2-trichloro-1,2,2-trifluoroethane (8 ml), and thesolution was cooled to 0° C. Piperidinosulfur trifluoride (0.062 ml,0.47 mmol) was added thereto, and the mixture was stirred at roomtemperature for 5.5 hours. Then, triethylamine was added thereto, and asaturated potassium carbonate aqueous solution was added thereto. Theproduct was purified by silica gel column chromatography to obtain theabove identified compound (0.21 g).

¹ N-NMR(CDCl₃) δ-0.1-0.1(m, 12H), 0.5-0.7(m, 6H), 0.7-1.0(m, 36H),1.1-1.6(m, 9H), 1.9-2.7(m, 7H), 3.63(s, 3H), 3.85(l, J=6.5 Hz, 1H),4.1-4.2(m, 1H), 4.2-4.3(m, 1H), 5.35(dd, J=48, 7.5 Hz, 1H), 5.4-5.5(m,2H) ¹⁹ F-NMR(CDCl₃, CCl₃ F standard) -170.0 ppm m

Example 1-4 Preparation of5,6-dehydro-2,3-methylene-7β-fluoro-17,20-dimethylPFG₂ α methyl ester11,15-bis(t-butyldimethyl)silyl ether

The triethylsilyl ether (0.21 g, 0.27 mmol) prepared in Example 1-3 wasdissolved in ethanol (5 ml), and pyridinium p-toluene sulfonate (7 mg,0.027 mmol) was added at 0° C. The mixture was stirred at roomtemperature for 3 hours. A saturated sodium hydrogen carbonate aqueoussolution was added thereto, and the product was extracted withdichloroemthane. The extract was dried, concentrated and the purified bysilica gel column chromgatography to obtain the above identifiedcompound (95 mg).

¹ N-NMR(CDCl₃) δ-0.1-0.1(m, 12H, 0.8-1.0(m, 36H), 1.0-2.0(m, 13H),2.4-2.6(m, 2H), 3.12(dd, J=8.4, 11.2 Hz, 1H), 3.62(s, 3H), 4.0-4.2(m,2H), 4.2-4.4(m, 1H), 5.2-5.5(m, 3H) ¹⁹ F-NMR(CDCl₃, CCl₃ F standard)-169.3(dm, J=47.1 Hz)

Example 1-5 Preparation of 2,3-methylene-7β-fluoro-17,20-dimethylPGF₂ αmethyl ester 11,15-bis(t-butyldimethyl)silyl ether

The compound (95 mg, 0.15 mmol) prepared in Example 1-4 was dissolved inbenzene (2.5 ml) and cyclohexane (2.5 ml), and cyclohexene (0.15 ml, 1.0mmol) and a Lindlar catalyst (20 mg) were added thereto, followed byhydrogenation at 0° C. for 1.5 hours.

¹ NMR(CDCl₃) δ0.0-0.1(m, 12H), 0.6-1.0(m, 27H), 1.0-2.4(m, 16H), 3.70(s,3H), 4.0-4.2(m, 2H), 4.3-4.4(m, 1H) 5.2-5.7(m, 5H) ¹⁹ F-NMR(CDCl₃, CCl₃F standard) -167.0 ppm (d, J=48 Hz)

Example 1-6 Preparation of 2,3-methylene-7α-fluoro-17,20-dimethylPGI₂methyl ester 11,15-bis(t-butyldimethyl)silyl ether

The olefin (100 mg, 0.15 mmol) prepared in Example 1-5 was dissolved inacetonitrile (4 ml), and N-iodosuccinic imide (0.49 g, 2.2 mmol) wasadded, and the mixture was stirred at 40° C. for 24 hours. Then, 10%sodium thiosulfate was added, and the product was extracted withdichloromethane. The organic layer was dried, concentrated and purifiedby silica gel chromatography to obtain a cyclized product (83 mg).

The above cyclized product (83 mg) was dissolved in toluene (5 ml), and1,8-diazobicyclo[5.4.0]-7-undecene (0.15 ml) was added thereto. Themixture was stirred at 110° C. for 18 hours. A saturated sodium chlorideaqueous solution was added thereto, and the product was extracted withethyl ether. The organic layer was dried, concentrated and then purifiedby silica gel column chromatography to obtain the above identifiedcompound (14 mg).

¹ N-NMR(CDCl₃) δ-0.1-0.1(m, 12H), 0.7-1.0(m, 27H), 1.0- 1.8(m, 12H),2.0-2.2(m, 1H, H-4), 2.3-2.4(m, 1H, H-10), 2.4-2.6(m, 1H, H-8,2.7-2.8(m, 1H, H-12), 3.62(,s, 3H), 3.8-3.9(m, 1H, H-11), 4.1-4.2(m, 1H,H-15), 4.5-4.6(m, 2H, H-5, H-9), 5,32(dd, J=53, 7.5 Hz, 1H), 5.4-5.6(m,2H) ¹⁹ F-NMR(CDCl₃, CCl₃ F standard) -184.0 ppm (d, J=53 Hz, 0.5F),184.2 ppm (d, J=51.7 Hz, 0.5F)

Example 1-7 Preparation of 2,3-methylene-7α-fluoro-17,20-dimethyl PGI₂methyl ester

The t-butyldimethylsilyl ether product (13 mg) prepared in Example 1-6was dissolved in tetrahydrofuran (1 ml), and tetrabutyl ammoniumfluoride (factor=1, a tetrahydrofuran solution, 0.16 ml, 0.16 mmol) wasadded thereto at 0° C. The mixture was stirred at room temperature for 3hours. Then, a saturated ammonium sulfate solution was added thereto,and the product was extracted with ethyl acetate. The organic layer wasdried, concentrated and purified by a florisil column to obtain theabove identified compound (9 mg).

¹ N-NMR(CDCl₃) δ0.7-1.0(m, 9H), 1.0-1.9(m, 11H), 2.4-2.8(m, 5H), 3.60(s,3H), 3.85(l, J=7.5 Hz, 1H), 4.10(l, J=6.5 Hz, 1H), 4.5-4.6(m, 2H),5.35(dm, 1H), 5.5-5.69(m, 2H) ¹⁹ F-NMR(CDCl₃, CCl₃ F standard) -186.0ppm (d, J=55.0 Hz, 0.5F), -188.0 ppm (d, J=55.5 Hz, 0.5F)

Example 1-8 Preparation of sodium salt of2,3-methylene-7α-fluoro-17,20-dimethylPGI₂

The methyl ester (9 mg) prepared in Example 1-7 was dissolved in ethanol(0.30 ml), and 0.1N sodium hydroxide (0.28 ml) was added thereto. Themixture was stirred at 25° C. for 36 hours. The product was concentratedand dried to obtain the above identified compound.

EXAMPLE 2 Sodium salt of4-homo-2,3-methylene-7α-fluoro-17,20,-dimethylPGI₂ Example 2-1Preparation of5,6-dehydro-4-homo-2,3-methylene-7-hydroxy-17,20-dimethylPGE₂ methylester 11,15-bis(t-butyldimethyl)silyl ether

t-Butyllithium (factor=1.5, a pentane solution, 2.7 ml, 4.0 mmol) wasadded to ethyl ether (5 ml) at -78° C.(1E,3S,5S)-3-t-butyldimethylsiloxy-5-methyl-1-iodo-1-nonene (0.79 g, 2.0mmol) was dissolved in ethyl ether (5 ml) and dropwise added theretoover a period of 10 minutes. The mixture was stirred for two hours at-78° C. Then, pentyne copper (0.26 g, 2.0 mmol) and HMPT (0.65 g, 4.0mmol) were dissolved in ethyl ether (10 ml) and dropwise added theretoover a period of 15 minutes. One hour and thirty minutes later,(4R)-4-t-butyldimethylsiloxy-2-cyclopentenone (0.40 g, 1.9 mmol) wasdissolved in ethyl ether (10 ml) and added thereto. Twenty minuteslater, the temperature was raised to -40° C. Further,2-(5-oxo-3-pentynyl)cyclopropane carboxylic acid methyl ester (0.35 g,2.0 mmol) was dissolved in ethyl ether (10 ml) and dropwise addedthereto over a period of 15 minutes. The mixture was stirred for onehour at -40° C. Then, a saturated ammonium chloride aqueous solution wasadded thereto, and the product was extracted with ethyl ether. It wasthen purified by silica gel column chromatography to obtain the aboveidentified compound (0.66 g, yield: 53%).

¹ N-NMR(CDCl₃) δ-0.1-0.1(m, 12H), 0.6-1.0(m, 27H), 1.0-1.5(m, 11H),2.1-2.4(m, 7H), 2.6-2.8(m, 2H), 3.62(s, 3H), 4.0-4.2(m, 2H), 5.5-5.6(m,2H)

Example 2-2 Preparation of5,6-dehydro-4-homo-2,3-methylene-7-trimethylsiloxy-17,20-dimethylPGF₂ αmethyl ester 11,15-bis(t-butyldimethyl)silyl ether

Using the alcohol (0.66 g, 1.0 mmol) prepared in Example 2-1, the aboveidentified compound (0.59 g) was obtained in the same manner as inExample 1-2.

Example 2-3 Preparation of5,6-dehydro-4-homo-2,3-methylene-7α-fluoro-17,20-dimethylPGF₂ α methylester 11,15-bis(t-butyldimethyl)silyl-9-triethylsilyl ether

Using the trimethylsilyl ether (0.59 g, 0.70 mmol) prepared in Example2-2, fluorination was conducted in the same manner as in Example 1-3 toobtain the above identified compound (0.39 g).

¹ N-NMR(CDCl₃) δ-0.1-0.1(m, 12H), 0.5-0.6(m, 6H), 0.7-1.0(m, 36H),1.1-1.6(m, 11H), 1.8-2.4(m, 6H), 2.6-2.7(m, 1H), 3.63(s, 3H), 3.86(l,J=6.5 Hz, 1H), 4.1-4.2(m, 1H), 4.2-4.3(m, 1H), 5.32(dd, J=49, 7.5 Hz,1H), 5.4-5.6(m, 2H) ¹⁹ F-NMR(CDCl₃, CCl₃ F standard) -169.6 ppm(m)

Example 2-4 Preparation of5,6-dehydro-4-homo-2,3-methylene-7β-fluoro-17,20-dimethylPGF₂ α methylester 11,15-bis(t-butyldimethyl)silyl ether

Using the triethylsilyl ether (0.39 g, 0.50 mmol) prepared in Example2-3, the above identified compound (2.04 g) was prepared in the samemanner as in Example 1-4.

Example 2-5 Preparation of4-homo-2,3-methylene-7β-fluoro-17,20-dimethylPGF₂ α methyl ester11,15-bis(t-butyldimethyl)silyl ether

Using the acetylene (0.24 g) prepared in Example 2-4, the aboveidentified compound (0.21 g) was obtained in the same manner as inExample 1-5.

¹ N-NMR(CDCl₃) δ0.0-0.1(m, 12H), 0.6-1.0(m, 27H), 1.0- 2.4(m, 18H),3.65(s, 3H), 4.0-4.2(m, 2H), 4.3-4.4(m, 1H), 5.2-5.7(m, 5H) ¹⁹F-NMR(CDCl₃, CCl₃ F standard) -167.2 ppm (d, J=56 Hz)

Example 2-6 Preparation of4-homo-2,3-methylene-7α-fluoro-17,20-dimethyl-PGF₂ methyl ester11,15-bis(t-butyldimethyl)silyl ether

Using the olefin (0.21 g, 0.35 mmol) prepared in Example 2-5, the aboveidentified compound (34 mg) was prepared in the same manner as inExample 1-6.

¹ N-NMR(CDCl₃) δ-0.1-0.1(m, 12H), 0.6-1.0(m, 27H), 1.0-1.8(m, 13H),2.0-2.2 (m, 2H), 2.3-2.4(m, 1H), 2.4-2.6(s, 1H), 2.7-2.8(m, 1H), 3.62(s,3H), 3.80(l, J=7.5 Hz, 7.5 Hz, 1H), 4.1-4.2(m, 1H), 4.5--4.5(m, 2H),5.28(dd, J=56, 7.5 Hz, 1H), 5.4-5.6(m, 2H) ¹⁹ F-NMR(CDCl₃, CCl₃ Fstandard) -182.6 ppm (d, J=56 Hz)

Example 2-7 Preparation of4-homo-2,3-methylene-7α-fluoro-17,20-dimethylPGI₂ methyl ester

Using the silyl ether product (34 mg) prepared in Example 2-6, the aboveidentified compound (24 mg) was prepared in the same manner as inExample 1-7.

¹ N-NMR(CDCl₃) δ0.7-1.0(m, 6H), 0.87(d, J=6.3 Hz, 3H), 1.0-1.9(m, 13H),2.4-3.0(m, 5H), 3.66(s, 1.5H), 3.67(s, 1.5H), 3.8-3.9(m, 1H), 4.1-4.2(m,1H), 4.5-4.7(m, 1H), 5.40(d, J= 55Hz, 1H), 5.56(d, J=4.1 Hz, 1H) ¹⁹F-NMR(CDCl₃, CCl₃ F standard) -187.0 ppm (d, J=57.0 Hz, 0.5F), -187.3ppm(d, J=54.7 Hz), 0.5F)

Example 2-8 Preparation of sodium salt of4-homo-2,3-methylene-7α-fluoro-17,20-dimethylPGI₂

The methyl ester (24 mg, 0.06 mmol) prepared in Example 2-7, wasdissolved in ethanol (0.73 ml), and 0.1N sodium hydroxide (0.68 ml) wasadded thereto. The mixture was stirred at 25° C. for 48 hours. Then, itwas concentrated and dried to obtain the above identified compound.

EXAMPLE 3 (1S*,3S*)-2,3-ethylene-7α-fluoro-17,20-dimethylPGI₂ methylester and sodium salt Example 3-1 Preparation of(1S*,3S*)-2,4-ethylene-5,6-dehydro-7-hydroxy-17,20-dimethyl-PGI₂ -methylester 11,15-bis(t-butyldimethyl)silyl ether

Using the aldehyde (1.36 g, 7.56 mmol) prepared in Reference Example 14,the above identified compound (3.07 g, yield: 67.2%) was prepared in thesame manner as in Example 1-1.

¹ N-NMR(CDCl₃) δ0.00-0.20(m, 12H), 0.80-1.00(m, 24H), 3.69(s, 3H),4.15-4.25(m, 2H), 5.54-5.70(m, 2H)

Example 3-2 Preparation of(1S*,3S*)-2,4-ethylene-5,6-dehydro-7-trimethylsiloxy-17,20-dimethylPGF.sub.2α methyl ester 11,15-bis(t-butyldimethyl)silyl ether

Using the compound (3.07 g, 4.62 mmol) prepared in Example 3-1, theabove identified compound (2.77 g, yield: 70.5%) was prepared in thesame manner as in Example 1-2.

¹ N-NMR(CDCl₃) δ0.00-0.20(m, 21H), 0.50-0.70(m, 6H), 0.80-1.00(m, 30H),3.68(s, 3H), 4.15-4.25(m, 2H), 5.50-5.70(m, 2H)

Example 3-3 Preparation of(1S*,3S*)-2,4-ethylene-5,6-dehydro-7β-fluoro-17,20-dimethylPGF₂ α methylester 11,15-bis(t-butyldimethyl)silyl-9-triethylsilyl ether

Using the compound (2.77 g, 3.26 mmol) prepared in Example 3-2, theabove identified compound (2.15 g, yield: 84.9% was prepared in the samemanner as in Example 1-3.

¹ N-NMR(CDCl₃) δ0.00-0.20(m, 12H), 0.50-0.70(m, 6H), 0.80-1.00(m, 30H),3.68(s, 3H), 4.15-4.25(m, 2H), 5.40-5.70(m, 3H) ¹⁹ F-NMR(CDCl₃ CCl₃ Fstandard) -169.0 ppm(m)

Example 3-4 Preparation of(1S*,3S*)-2,4-ethylene-5,6-dehydro-7β-fluoro-17,20-dimethylPGF₂ α methylester 11,15-bis(t-butyldimethyl)silyl ether

Using the compound (2.15 g, 2.77 mmol) prepared in Example 3-3, theabove identified compound (1.13 g, mmol, yield: 61.5%) was prepared inthe same manner as in Example 1-4.

¹ N-NMR(CDCl₃) δ0.00-0.20(m, 12H), 0.80-1.00(m, 24H), 3.68(s, 3H),4.08-4.24(m, 2H), 5.28-5.56(m, 3H) ¹⁹ F-NMR(CDCl₃, CCl₃ F standard)-169.0 ppm(m)

Example 3-5 Preparation of(1S*,3S*)-2,4-ethylene-7α-fluoro-17,20-dimethyl-PGI₂ methyl ester11,15-bis(t-butyldimethyl)silyl ether

Using the compound (1.13 g, 1.70 mmol) prepared in Example 3-4, theabove identified compound was prepared in the same manner as in Example1-5 and Example 1-6. Low polarity isomer (127 mg, yield: 11.2%), and thehigh polarity isomer (67 mg, yield: 5.9%).

Low polarity isomer: ¹ N-NMR(CDCl₃) δ0.00-0.10(m, 12H), 0.80-0.90(m,24H), 3.63(s, 3H), 5.26(dd, J=56 Hz, J=9 Hz, 1H), 5.50-5.55(m, 2H) ¹⁹F-NMR(CDCl₃, CCl₃ F standard) -183.4 ppm(dd, J=56 Hz, 9 Hz)

High polarity isomer: ¹ N-NMR(CDCl₃) δ0.02(s, 12H), 0.84-0.88(m, 24H),3.65(s, 3H), 5.26(dd, J=56 Hz, J=9 Hz), 5.50-5.55(m, 2H) ¹⁹ F-NMR(CDCl₃,CCl₃ F standard) -183.4 ppm(dd, J=56 Hz, 9 Hz)

Example 3-6 Preparation of(1S*,3S*)-2,4-ethylene-7α-fluoro-17,20-dimethylPGI₂ -methyl ester

Using the compounds prepared in Example 3-5 i.e. the low polarity isomer(127 mg, 0.19 mmol) and the high polarity isomer (67 mg, 0.10 mmol), theabove identified compounds were obtained in the same manner as inExample 1-7. The low polarity isomer (58 mg, yield: 70.2%), and the highpolarity isomer (33 mg, yield: 75.1%).

Low polarity isomer: ¹ N-NMR(CDCl₃) δ0.80-0.95(m, 6H), 3.67(s, 3H),3.80-3.95(m, 4.10-4.20(m, 1H), 4.55-4.65(m, 2H), 5.35(dd, J=56 Hz, 9 Hz,1H), 5.50-5.60(m, 2H) ¹⁹ F-NMR(CDCl₃, CCl₃ F standard) -185.6 ppm(dd,J=56 Hz, 9 Hz)

High polarity isomer: ¹ N-NMR(CDCl₃) δ0.80-0.95(m, 6H), 6.67(s, 3H),3.80-3.95(m, 1H0, 4.10-4.20(m, 1H), 4.50-5.65(m, 1H), 4.10-4.20(m, 1H),4.50-4.65(m, 2H), 5.35(dd, J=56 Hz, 9 Hz), 5.55-5.60(m, 2H) ¹⁹F-NMR(CDCl₃, CCl₃ F standard) -184.9 ppm(dd, J=56 Hz, 9 Hz)

Example 3-7 Preparation of sodium salt of(1S*,3S*)-2,4-ethylene-7α-fluoro-17,20-dimethyl-PGI₂

Using the low polarity isomer (96 mg) among the compounds prepared inExample 3-6, the low polarity isomer (38 mg) of the above identifiedcompound was prepared in the same manner as in Example 1-8. Further,using the high polarity isomer (87 mg) among the compounds prepared inExample 3-6, the high polarity isomer (69 mg) of the above identifiedcompound was prepared in the same manner as in Example 1-8.

Low polarity isomer: ¹ N-NMR(CDCl₃) δ0.92-1.05(m, 6H), 3.90-4.00(m, 1H),4.12-4.25(m, 1H), 4.58-4.72(m, 2H) 5.45(dd, J=64 Hz, 8.4 Hz, 1H),5.56-5.80(m, 2H) ¹⁹ F-NMR(CDCl₃, CCl₃ F standard) -186.0 ppm(d, 64 Hz)

High polarity isomer: ¹ N-NMR(CDCl₃) δ0.90-1.05(m, 6H), 3.88-4.02(m,1H), 4.14(4.24(m, 1H), 4.58-4.70(m, 2H), 5.45(dd, J=64 Hz, 8.4 Hz, 1H),5.55-5.80(m, 2H) ¹⁹ F-NMR(CDCl₃, CCl₃ F standard) -185.4 ppm(d, 64 Hz)

EXAMPLE 4 (1S*,3R*)-2,4-ethylene-7α-fluoro-17,20-dimethylPGI₂ methylester Example 4-1 Preparation of(1S*,3R*)-2,4-ethylene-5,6-dehydro-7-hydroxy-17,20-dimethylPGE₂ methylester-11,15-bis(t-butyldimethyl)silyl ether

Using the aldehyde (1.09 g, 6.05 mmol) prepared in Reference Example 17,the above identified compound (2.28 g, yield: 62.2%) was prepared in thesame manner as in Example 1-1

¹ N-NMR(CDCl₃) δ0.00-0.20(m, 12H), 0.80-1.00(m, 24H), 3.67(s, 3H),4.16-4.30(m, 2H), 5.50-5.70(m, 2H)

Example 4-2 Preparation of(1S*,3R*)-2,4-ethylene-5,6-dehydro-7-trimethylsiloxy-17,20-dimethylPGF.sub.2α methyl ester-11,15-bis(t-butyldimethyl)silyl ether

Using the compound (2.28 g, 3.42 mmol) prepared in Example 4-1, theabove identified compound (1.98 g, yield: 68.1%) was prepared in thesame manner as in Example 1-2.

¹ N-NMR(CDCl₃) δ0.00-0.10(m, 21H), 0.50-0.65(m, 6H), 0.28-1.00(m, 30H),3.67(s, 3H), 5.40-5.60(m, 2H)

Example 4-3 Preparation of(1S*,3R*)-2,4-ethylene-5,6-dehydro-7β-fluoro-17,20-dimethylPGF₂ α methylester-11,15-bis(t-butyldimethyl)silyl-9-triethylsilyl ether

Using the compound (1.98 g, 2.33 mmol) prepared in Example 4-2, theabove identified compound (1.55 g, yield: 85.4%) was prepared in thesame manner as in Example 1-3.

¹ N-NMR(CDCl₃) δ0.00-0.10(m, 12H), 0.50-0.70(m, 6H), 0.80-1.00(m, 30H),3.68(s, 3H), 5.20-5.60(m, 3H) ¹⁹ F-NMR(CDCl₃, CCl₃ F standard) -169.8ppm (m)

Example 4-4 Preparation of(1S*,3R*)-2,4-ethylene-5,6-dehydro-7β-fluoro-17,20-dimethylPGF₂ α methylester-11,15-bis(t-butyldimethyl)silyl ether

Using the compound (1.55 g, 1.99 mmol) prepared in Example 4-3, theabove identified compound (845 mg, yield: 64.0%) was prepared in thesame manner as in Example 1-4.

¹ N-NMR(CDCl₃) δ0.00-0.15(m, 12H), 0.85-0.95(m, 24H), 3.68(s, 3H),4.10-4.20(m, 2H), 5.30-5.55(m, 3H) ¹⁹ F-NMR(CDCl₃, CCl₃ F standard)-169.0 ppm (dd, J=56 Hz, 9 Hz)

Example 4-5 Preparation of(1S*,3R*)-2,4-ethylene-7α-fluoro-17,20-dimethyl-PGI₂ α methylester-11,15-bis(t-butyldimethyl)silyl ether

Using the compound (845 mg, 1.27 mmol) prepared in Example 4-4, theabove identified compound (205 mg, yield: 24.3%) was prepared in thesame manner as in Example 1-5 followed by Example 1-6.

¹ N-NMR(CDCl₃) δ0.00-0.20(m, 12H), 0.80-0.95(m, 24H), 3.67(s, 3H),5.30(dd, J=56 Hz, 1H), 5.55-5.60(m, 2H) ¹⁹ F-NMR(CDCl₃, CCl₃ F standard)-182.4 ppm(dd, J=56 Hz, 9 Hz), -182.8 ppm(dd, J=56 Hz, 9 Hz)

Example 4-6 Preparation of(1S*,3R*)-2,4-ethylene-7α-fluoro-17,20-dimethyl-PGI₂ methyl ester

Using the compound (205 mg, 0.31 mmol) prepared in Example 4-5, theabove identified compound (118 mg, yield: 87.5%) was prepared in thesame manner as in Example 1-7.

¹ N-NMR(CDCl₃) δ0.85-1.00(m, 6H), 3.67(s, 3H), 3.85-3.95(m, 1H),4.15-4.25(m, 1H), 4.55-4.65(m, 1H), 5.38(dd, J=56 Hz, 9 Hz, 1H),5.55-5.65(m, 2H) ¹⁹ F-NMR(CDCl₃, CCl₃ F standard) -184.5 ppm(dd, J=56Hz, 9 Hz), -185.1 ppm(dd, J=56 Hz, 9 Hz)

EXAMPLE 5 2,4-ethylene-3α-homo-7α-fluoro-17,20-dimethylPGI₂ methyl esterExample 5-1 Preparation of2,4-ethylene-3α-homo-5,6-dehydro-7-hydroxy-17,20-dimethylPGE₂ methylester 11,15-bis(t-butyldimethyl)silyl ether

Using the aldehyde (3.68 g, 19.9 mmol) prepared in Reference Example 24,the above identified compound (5.41 g, yield: 44%) was prepared in thesame manner as in Example 1-1.

Example 5-2 Preparation of2,4-ethylene-3α-homo-5,6-dehydro-7-trimethylsiloxy-17,20-dimethylPGF₂ αmethyl ester 11,15-bis(t-butyldimethyl)silyl ether

Using the aldehyde (5.41 g, 7.99 mmol) prepared in Example 5-1, theabove identified compound (4.39 g, yield: 64%) was prepared in the samemanner as in Example 1-2.

¹ N-NMR(CDCl₃) δ3.67(s, 3H), 5.4-5.7(m, 2H)

Example 5-3 Preparation of2,4-ethylene-3α-homo-5,6-dehydro-7β-fluoro-17,20-dimethylPGF.sub.2 αmethyl ester 11,15-bis(t-butyldimethyl)silyl-9-triethylsilyl ether

Using the compound (4.39 g, 5.07 mmol) prepared in Example 5-2, theabove identified compound (2.60 g, yield: 68%) was prepared in the samemanner as in Example 1-3.

Example 5-4 Preparation of2,4-ethylene-3α-homo-5,6-dehydro-7β-fluoro-17,20-dimethylPGF.sub.2 αmethyl ester 11,15-bis(t-butyldimethyl)silyl ether

Using the compound (2.60 g, 3.27 mmol) prepared in Example 5-3, theabove identified compound (1.31 g, yield: 59%) was prepared in the samemanner as in Example 1-4.

¹ N-NMR(CDCl₃) δ3.67(m, 3H), 5.45(m, 2H) ¹⁹ F-NMR(CDCl₃, CCl₃ Fstandard) -168.4 ppm(m)

Example 5-5 Preparation of2,4-ethylene-3α-homo-7α-fluoro-17,20-dimethylPGI₂ methyl ester11,15-bis(t-butyldimethyl)silyl ether

Using the compound (1.31 g, 1.92 mmol) prepared in Example 5-4, twotypes of isomers of the above identified compound i.e. a low polarityisomer (115 mg, yield: 8.8%) and a high polarity isomer (102 mg, yield:7.8%) were prepared in the same manner as in Example 1-5, followed byExample 1-6.

Low polarity isomer: ¹ N-NMR(CDCl₃) δ3.67(s, 3H), 5.54(m, 1H) ¹⁹F-NMR(CDCl₃, CCl₃ F standard) -182.2 ppm(m)

High polarity isomer: ¹ N-NMR(CDCl₃) δ3.66(s, 3H), 5.3(m, 1H), 5.54(m,1H) ¹⁹ F-NMR(CDCl₃, CCl₃ F standard) -182.7 ppm(m)

Example 5-6 Preparation of2,4-ethylene-3α-homo-7α-fluoro-17,20-dimethylPGI₂ methyl ester

Using the low polarity isomer (115 mg, 0.17 mmol) among the compoundsprepared in Example 5-5, the above identified compound (57 mg, yield:75%) was prepared in the same manner as in Example 1-7. Using the highpolarity isomer (102 mg, 0.15 mmol) among the compounds prepared inExample 5-5, the above identified compound (62 mg, yield: 91%) wasprepared in the same manner as in Example 1-7.

Low polarity isomer: ¹ N-NMR(CDCl₃) δ0.8-2.8(m, 29H), 3.68(s, 3H),3.90(m, 1H), 4.18(m, 1H0, 4.64(m, 2H), 5.37(m, 1H), 5.59(m, 2H) ¹⁹F-NMR(CDCl₃, CCl₃ F standard) -184.5 ppm(m)

High polarity isomer: ¹ N-NMR(CDCl₃) δ0.8-2.8(m, 29H), 3.66(s, 3H),3.90(m, 1H), 4.15(m, 1H), 4.4-4.7-(m, 2H), 5.38(m, 2H) ¹⁹ F-NMR(CDCl₃,CCl₃ F standard) -184.8 ppm(m)

REFERENCE EXAMPLE 25 Preparation of3-(t-butyldimethylsiloxymethyl)cyclohexanecarboaldehyde

Using 1,3-cyclohexanedimethanol (48 g), the above identified compound(31 g) was prepared in the same manner as in Reference Example 18.

¹ N-NMR(CDCl₃) δ0-0.1(m, 6H), 0.7-0.9(m, 9H), 1.0-2.4(m, 8H), 3.4-3.6(m,2H), 9.6(s, 1H)

REFERENCE EXAMPLE 26 Preparation of3-(2,2-dibromovinyl)cyclohexanemethanol t-butyldimethylsilyl ether

Using the compound (14 g) prepared in Reference Example 25, the aboveidentified compound (16 g) was prepared in the same manner as inReference Example 19.

¹ N-NMR(CDCl₃) δ0-0.1(m, 6H), 0.7-0.9(m, 9H), 1.2-1.8(m, 8H), 3.3-3.5(m,2H), 6.2(m, 1H)

REFERENCE EXAMPLE 27 Preparation of3-(3-tetrahydropyranyloxy-1-propynyl)cyclohexanemethanolt-butyldimethylsilyl ether

Using the compound (16 g) prepared in Reference Example 26, the aboveidentified compound (11.6 g) was prepared in the same manner as inReference Example 20.

¹ N-NMR(CDCl₃) δ0-0.1(m, 6H), 0.8-0.9(m, 9H), 1.2-2.3(m, 14H),3.3-3.4(m, 2H), 3.4-3.6(m, 1H), 3.8-3.9(m, 1H), 4.1-4.3(m, 2H),4.8-4.9(m, 1H)

REFERENCE EXAMPLE 28 Preparation of3-(3-tetrahydropyranyloxy-1-propynyl)cyclohexanemethanol

Using the compound (11.6 g) prepared in Reference Example 27, the aboveidentified compound (7.8 g) was prepared in the same manner as inReference Example 21.

REFERENCE EXAMPLE 29 Preparation of3-(3-tetrahydropyranyloxy-1-propynyl)cyclohexanecarboaldehyde

Using the compound (7.8 g) prepared in Reference Example 28, the aboveidentified compound (6.0 g) was prepared in the same manner as inReference Example 22.

¹ N-NMR(CDCl₃) δ1.2-2.4(m, 14H), 3.4-3.6(m, 1H), 3.8-3.9(m, 1H),4.2-4.4(m, 2H), 4.8-4.9(m, 1H), 9.6(m, 1H)

REFERENCE EXAMPLE 30 Preparation of3-(3-hydroxy-1-propynyl)cyclohexanecarboxylic acid methyl ester

Using the compound (9 g) prepared in Reference Example 29, the aboveidentified compound (3.8 g) was prepared in the same manner as inReference Example 23.

¹ N-NMR(CDCl₃) δ1.2-2.4(m, 8H), 3.7(s, 3H), 4.2-4.3(m, 2H)

REFERENCE EXAMPLE 31 Preparation of3-(3-oxo-1-propynyl)cyclohexanecarboxylic acid methyl ester

Using the compound (3.8 g) prepared in Reference Example 30, the aboveidentified compound (3.1 g) was prepared in the same manner as inReference Example 24.

¹ N-NMR(CDCl₃) δ1.2-2.6(m, 8H), 3.7(s, 3H), 9.2(m, 1H)

EXAMPLE 6 2,4-propylene-7α-fluoro-17,20-dimethylPGI₂ methyl esterExample 6-1 Preparation of2,4-propylene-5,6-dehydro-7-hydroxy-17,20-dimethylPGE₂ methyl ester11,15-bis(t-butyldimethyl)silyl ether

Using the aldehyde (0.92 g) prepared in Reference Example 31, the aboveidentified compound (1.50 g) was prepared in the same manner as inExample 1-1.

Example 6-2 Preparation of2,4-propylene-5,6-dehydro-7-trimethylsiloxy-17,20-dimethylPGF₂ α methylester (11,15-bis(t-butyldimethyl)silyl-9-triethylsilyl ether

Using the compound (1.50 g) prepared in Example 6-1, the aboveidentified compound (1.47 g) was prepared in the same manner as inExample 1-2.

¹ N-NMR(CDCl₃) δ0.00-0.20(m, 21H), 0.50-0.70(m, 6H), 0.80-1.00(m, 33H),3.58(s, 3H), 3.98-4.15(m, 2H), 5.32-5.60(m, 2H)

Example 6-3 Preparation of2,4-propylene-5,6-dehydro-7β-fluoro-17,20-dimethylPGF₂ α methyl ester11,15-bis(t-butyldimethyl)silyl-9-triethylsilyl ether

Using the compound (1.47 g) prepared in Example 6-2, the aboveidentified compound (0.90 g) was prepared in the same manner as inExample 1-3.

¹⁹ F-NMR(CDCl₃, CCl₃ F standard) -169.5 ppm(m)

Example 6-4 Preparation of2,4-propylene-5,6-dehydro-7β-fluoro-17,20-dimethylPGF₂ α methyl ester11,15-bis(t-butyldimethyl)silyl ether

Using the compound (0.90 g) prepared in Example 6-3, the aboveidentified compound (488 mg) was prepared in the same manner as inExample 1-4.

¹ N-NMR(CDCl₃) δ0.00-0.12(m, 12H), 0.80-1.00(m, 24H), 3.61(s, 3H),4.00-4.18(m, 2H), 5.22-5.54(m, 2H) ¹⁹ F-NMR(CDCl₃, CCl₃ F standard)-168.6 ppm(m)

Example 6-5 Preparation of 2,4-propylyene-7α-fluoro-17,20-dimethylPGI₂methyl ester 11,15-bis(t-butyldimethyl)silyl ether

Using the compound (488 mg) prepared in Example 6-4, two types ofisomers of the above identified compound i.e. a low polarity isomer (53mg) and a high polarity isomer (48 mg) were prepared in the same manneras in Example 1-5, followed by Example 1-6.

Low polarity isomer: ¹ N-NNR(CDCl₃) δ0.00-0.20(m, 12H), 0.80-0.90(m,24H), 2.59(s, 3H), 5.22(dd, J=57.9 Hz, 9 Hz, 1H), 5.42-5.48(m, 2H) ¹⁹F-NMR(CDCl₃, CCl₃ F standard) -182.9 ppm(dd, J=60 Hz, 10 Hz)

High polarity isomer: ¹ N-NMR(CDCl₃) δ0.00-0.15(m, 12H), 0.78-0.90(m,24H), 3.61(s, 3H), 5.22(dd, J=60 Hz, 9 Hz, 1H), 5.42-5.48(m, 2H) ¹⁹F-NMR(CDCl₃, CCl₃ F standard) -182.4 ppm(dd, J=60 Hz, 10 Hz)

Example 6-6 Preparation of 2,4-propylyene-7α-fluoro-17,20-dimethylPGI₂methyl ester

Using the low polarity isomer (53 mg) among the compounds prepared inExample 6-5, the above identified compound (27 mg) was prepared in thesame manner as in Example 1-7. Using the high polarity isomer (48 mg)among the compound prepared in Example 6-5, the above identifiedcompound (25 mg) was prepared in the same manner as in Example 1-7.

Low polarity isomer: ¹ N-NMR(CDCl₃) δ0.88-.0.96(m, 6H), 3.65(s, 3H),3.82-4.00(m, 1H), 4.16-4.24(m, 1H), 4.46-4.52(m, 1H), 4.60-4.70(m, 1H),5.38(dd, J=57 Hz, 9 Hz), 5.56-5.64(m, 2H) ¹⁹ F-NMR(CDCl₃, CCl₃ Fstandard) -184.8 ppm(dm, J=57 Hz) -186.8 ppm(dm, J=57 Hz)

High polarity isomer: ¹ N-NMR(CDCl₃) δ0.88-0.92(m, 6H), 3.65(s, 3H),3.82-4.00(m, 1H), 4.16-4.24(m, 1H), 4.46-4.52(m, 1H), 4.60-4.70(m, 1H),5.28(dd, J=58 Hz, 10 Hz, 1H), 5.58-5.61(m, 2H) ¹⁹ F-NMR(CDCl₃, CCl₃ Fstandard) -184.2 ppm(dm, J=58 Hz) -184.4 ppm(dm, J=58 Hz)

REFERENCE EXAMPLE 32 Preparation of3(t-butyldimethylsiloxymethyl)cyclobutanecarbaldehyde

Using 1,3-cyclobutanedimethanol (4.11 g), the above identified compound(3.61 g) was prepared in the same manner as in Reference Example 18.

¹ N-NMR(CDCl₃) δ0.07-0.13(m, 6H), 0.96(s, 9H), 1.98-2.60(m, 5H),2.98-3.15(m, 1H), 3.51(d, J=5.4 Hz, 0.5H), 3.61(d, J=5.4 Hz, 0.5H),9.67(d, J=3.2 Hz, 0.5H), 9.79(d, J=3.2 Hz, 0.5)

REFERENCE EXAMPLE 33 Preparation of3-(2,2-dibromovinyl)cyclobutanemethanol t-butyldimethylsilyl ether

Using the compound of (3.61 g) prepared in Reference Example 32, theabove identified compound (5.35 g) was prepared in the same manner as inReference Example 19.

¹ N-NMR(CDCl₃) δ0.04(s, 3H), 0.06(s, 3H), 0.90(s, 9H), 1.80-2.50(m, 5H),2.90-3.20(m, 1H), 3.50(d, J=5.1 Hz, 0.5H), 3.62(d, J=5.1 Hz, 0.5H),6.44(d, J=8.4 Hz, 0.5H)

REFERENCE EXAMPLE 34 Preparation of3-(3-tetrahydropyranyloxy-1-propynyl)cyclobutanemethhanolt-butyldimethylsilyl ether

Using the compound of (5.35 g) prepared in Reference Example 33, theabove identified compound (3.82 g) was prepared in the same manner as inReference Example 20.

¹ N-NMR(CDCl₃) δ0.04(s, 3H), 0.07(s, 3H), 0.90(s, 9H), 1.42-2.60(m,11H), 2.80-3.10(m, 1H), m, 1H), 3.48-3.60(m, 3H), 3.78-3.94(m, 1H),4.15-4.38(m, 2H), 4.78-3.84(m, 1H)

REFERENCE EXAMPLE 35 Preparation of3-(3-tetrahydropyranyloxy-1-propynyl)cyclobutanemethanol

Using the compound of (3.82 g) prepared in Reference Example 34, theabove identified compound (2.07 g) was prepared in the same manner as inReference Example 21.

¹ N-NMR(CDCl₃) δ1.40-2.65(m, 11H), 2.85(3.18(m, 1H), 3.50-3.70(m, 3H),3.78-3.90(m, 1H), 4.15-4.38(m, 2H), 4.75-5.05(m, 1H)

REFERENCE EXAMPLE 36 Preparation of3-(3-tetrahydropyranyloxy-1-propynyl)cyclobutanecarbaldehyde

Using the compound of (2.07 g) prepared in Reference Example 35, theabove identified compound (1.96 g) was prepared in the same manner as inReference Example 22.

¹ N-NMR(CDCl₃) δ1.40-1.90(m, 6H), 2.18-2.55(m, 4H), 2.95-3.18(m, 2H),3.46-3.60(m, 1H), 3.73-3.90(m, 1H), 4.12-4.36(m, 2H), 4.76(m, 1H),9.65(d, 2.2 Hz, 0.6H), 9.77(d, 2.2 Hz, 0.5H)

REFERENCE EXAMPLE 37 Preparation of3-(3-hydroxy-1-propynyl)cyclobutanecarboxylic acid methyl ester

Using the compound of (1.96 g) prepared in Reference Example 36, theabove identified compound (1.24 g) was prepared in the same manner as inReference Example 23.

¹ N-NMR(CDCl₃) δ2.25-2.26(m, 4H), 2.90-3.10(m, 1H), 3.12-3.28(m, 1H),3.68(s, 1.5H), 3.70(s, 1.5H), 2.47(m, 1H)

REFERENCE EXAMPLE 38 Preparation of3-(3-oxo-1-propynyl)cyclobutanecarboxylic acid methyl ester

Using the compound of (1.24 g) prepared in Reference Example 37, theabove identified compound (803 mg) was prepared in the same manner as inReference Example 24.

¹ N-NMR(CDCl₃) δ2.36-2.53(m, 2H), 2.60-2.75(m, 2H), 3.20-3.45(m, 2H),3.70(s, 3H), 9.21(s, 1H)

EXAMPLE 7 2,4-methylene-7α-fluoro-17,20-dimethylPGI₂ methyl ester andsodium salt Example 7-1 Preparation of2,4-methylene-5,6-dehydro-7-hydroxy-17,20-dimethylPGE₂ methyl ester11,15-bis(t-butyldimethyl)silyl ether

Using the compound (803 mg) prepared in Reference Example 38, the aboveidentified compound (1.60 g) was prepared in the same manner as inExample 1-1.

¹ N-NMR(CDCl₃) δ0.01(m, 12H), 0.80-0.95(m, 24H), 3.66(m, 3H),5.50-5.70(m, 2H)

Example 7-2 Preparation of2,4-methylene-5,6-dehydro-7-trimethylsiloxy-17,20-dimethylPGE₂ α methylester 11,15-bis(t-butyldimethyl)silyl-9-triethylsilyl ether

Using the compound (1.60 g) prepared in Example 7-1, the aboveidentified compound (1.54 g) was prepared in the same manner as inExample 1-2.

¹ N-NMR(CDCl₃) δ0-0.2(m, 12H), 0.45-1.00(m, 48H), 3.73(m, 3H),3.82-3.95(m, 1H), 4.10-4.25(m, 2H), 4.55-4.80(m, 2H), 5.40- 5.70(m, 2H)

Example 7-3 Preparation of2,4-methylene-5,6-dehydro-7β-fluoro-17,20-dimethylPGF₂ α methyl ester11,15-bis(t-butyldimethyl)silyl-9-triethylsilyl ether

Using the compound (1.54 g) prepared in Example 7-2, the aboveidentified compound (1.17 g) was prepared in the same manner as inExample 1-3.

¹ N-NMR(CDCl₃) δ0-0.20(m, 12H), 0.50-1.0(m, 33H), 3.73(s, 1.5H), 3.75(s,1.5H0, 3.85-3.95(m, 1H), 4.10-4.20(m, 1H), 4.21-4.35(m, 1H), 5.35(dm,J=46.6 Hz, 1H), 5.50(m, 2H) ¹⁹ F-NMR(CDCl₃, CCl₃ F standard) -170.1ppm(m)

Example 7-4 Preparation of2,4-methylene-5,6-dehydro-7β-fluoro-17,20-dimethylPGF₂ α methyl ester11,15-bis(t-butyldimethyl)silyl ether

Using the compound (1.17 g) prepared in Example 7-3, the aboveidentified compound (717 mg) was prepared in the same manner as inExample 1-4.

¹ N-NMR(CDCl₃) δ0-0.15(m, 12H), 0.75-0.95(m, 24H), 3.71(s, 1.5H),3.73(s, 1.5H), 4.08-4.20(m, 2H), 4.30-4.41(m, 1H), 5.40-5.50(m, 2H),5.47,(dm, J=46.6 Hz, 1H) ¹⁹ F-NMR(CDCl₃, CCl₃ F standard) -168.2 ppm(m)

Example 7-5 Preparation of 2,4-methylene-7α-fluoro-17,20-dimethylPGI₂methyl ester 11,15-bis(t-butyldimethyl)silyl ether

Using the compound (710 mg) prepared in Example 7-4, the aboveidentified compound (251 mg) was prepared in the same manner as inExample 1-5 followed by Example 1-6.

^(N-NMR)(CDCl₃) δ0-0.10(m, 12H), 0.75-0.95(m, 24H), 3.66(s, 1.5H),3.69(s, 1.5H), 3.75-3.90(m, 1H), 4.10-4.20(m, 1H), 4.48-4.80(m, 2H),5.30(dm, J=56.5 Hz, 1H) ¹⁹ F-NMR(CDCl₃, CCl₃ F standard) -183.8(dd,J=56.5 Hz, 7.5 Hz), -184.2(dd, J=56.5 Hz, 7.5 Hz)

Example 7-6 Preparation of 2,4-methylene-7α-fluoro-17,20-dimethylPGI₂methyl ester

Using the compound (251 mg) prepared in Example 7-5, the aboveidentified compound (132 mg) was prepared in the same manner as inExample 1-7. The obtained compound (132 mg) was subjected to highperformance liquid chromatography (silica, hexane:ethanol=96:4) toseparate two types of isomers, whereby a low polarity isomer (55 mg) anda high polarity isomer (67 mg) were obtained.

Low polarity isomer: ¹ N-NMR(CDCl₃) δ0.80-0.90(m, 6H), 3.55-3.60(m, 1H),3.60(s, 3H), 3.80-3.95(m, 1H), 4.05-4.15(m, 2H), 4.55-4.68(m, 2H),5.41(dd, J= 60 Hz, 8.3 Hz, 1H), 5.50-5.71(m, 2H) ¹⁹ F-NMR(CDCl₃, CCl₃ Fstandard) -184.8 ppm(dd, J=60 Hz, 8.1 Hz)

High polarity isomer: ¹ N-NMR(CDCl₃) δ0.80-0.90(m, 6H), 3.50-3.60(m,2H), 3.65(s, 3H), 3.80-3.98(m, 1H), 4.03-4.15(m, 2H), 4.58-4.66(m, 1H),4.70-4.80(m, 1H), 5.44(dd, J=60 Hz, 8.3 Hz, 1H), 5.50-5.70(m, 2H) ¹⁹F-NMR(CDCl₃, CCl₃ F standard) -184.8 ppm(dd, J=60 Hz, 8.3 Hz)

Example 7-7 Preparation of sodium salt of2,4-methylene-7α-fluoro-17,20-dimethylPGI₂

The low polarity isomer (158 mg) among the compounds prepared in Example7-6 was dissolved in ethanol (9.1 ml), and a 0.1N sodium hydroxideaqueous solution (3.94 ml) was added thereto under cooling with ice. Themixture was stirred at room temperature for 15 hours. The reactionsolution was concentrated under reduced pressure, and the residue wasdissolved in water (0.45 ml), and acetonitrile (13.8 ml) was added understirring. the precipitated white solid was collected by filtration anddried to obtain the low polarity isomer (128 mg) of the above identifiedcompound.

Using the high polarity isomer (188 mg) among the compounds prepared inExample 7-6, the high polarity isomer (156 mg) of the above identifiedcompound was prepared in the same manner as above.

Low polarity isomer: ¹ N-NMR(CDCl₃) δ0.94-1.05(m, 6H), 1.18-1.85(m,10H), 2.03-2.19(m, 2H0, 2,33-3.20(m, 7H), 3.86-4.00(m, 1H), 4.14-4.25(m,1H), 4.60-4.76(m, 2H), 5.45(dd, J=60 Hz, 8.4 Hz, 1H), 5.55-5.78(m, 2H)¹⁹ F-NMR(CDCl₃, CCl₃ F standard) -186.2 ppm(d, J=60 Hz)

High polarity isomer: ¹ N-NMR(CDCl₃) δ0.95-1.05(m, 6H), 1.18-1.82(m,10H), 2.00-2.20(m, 2H), 2.50-2.78(m, 5H), 3.00-3.20(m, 1H), 4.15-4.25(m,1H), 4.63-4.72(m, 1H), 4.86-4.94(m, 1H), 5.46(dd, J=60 Hz, 8.4 Hz, 1H),5.57-5.80(m, 2H) ¹⁹ F-NMR(CDCl₃, CCl₃ F standard) -186.0 ppm(d, J=60 Hz)

REFERENCE EXAMPLE 39 Preparation of3-(3-hydroxy-1-propynyl)cyclobutylacetic acid methyl ester

The compound (2.07 g) in Reference Example 35 was dissolved in methylenechloride (30 ml), and triethylamine (1.67 ml) and methane sulfonylchloride (0.79 ml) were added thereto. The mixture was stirred at roomtemperature for one hour. To the reaction solution, a saturated sodiumbicarbonate aqueous solution (20 ml) was added. Then, the organic layerwas separated and dried over anhydrous magnesium sulfate. Then, thesolvent was distilled off under reduced pressure. The residue therebyobtained was dissolved in N,N-dimethylformamide (50 ml) and water (10ml), and potassium cyanide (0.78 g) was added thereto. The mixture wasstirred at 80° C. for 7 hours. To the reaction solution, water (100 ml)was added, and the mixture was extracted with ethyl ether (20 ml×2). Theorganic layer was dried over anhydrous magnesium sulfate, and then thesolvent was distilled off under reduced pressure. The residue therebyobtained was dissolved in water (25 ml) and ethanol (25 ml), andpotassium hydroxide (807 mg) was added thereto, and the mixture wasstirred at 80° C. for 15 hours. Concentrated sulfuric acid was addedthereto to adjust the pH 2, and sodium chloride was saturated. Then, theproduct was extracted with methylene chloride (30 ml×2). The extract wasdried over anhydrous magnesium sulfate, and the solvent was distilledoff under reduced pressure. The residue thereby obtained was dissolvedin benzene (10 ml), and methanol (2 ml) and concentrated sulfuric acid(one drop) were added thereto. The solvent was distilled off underreduced pressure. The residue thereby obtained was purified by silicagel column chromatography to obtain the above identified compound (1.33g).

¹ N-NMR(CDCl₃) δ1.70-1.90(m, 1H), 1.95-2.10(m, 1H), 2.18-2.35(m, 1H),2.35-2.60(m, 3H), 2.75-3.14(m, 2H), 3.65(s, 1.5H), 3.66(s, 1.5H),4.23-4.30(m, 2H)

REFERENCE EXAMPLE 40 Preparation of 3-(3-oxo-1-propynyl)cyclobutylaceticacid methyl ester

Using the compound (1.33 g) prepared in Reference Example 39, the aboveidentified compound (1.26 g) was prepared in the same manner as inReference Example 24.

¹ N-NMR(CDCl₃) δ1.88-2.00(m, 1H), 2.05-2.20(m, 1H), 2.35-2.75(m, 4.5H),2.85-3.28(m, 1.5H), 3.66(s, 3H), 9.20(d, J=7.3 Hz, 1H)

EXAMPLE 8 1α-Homo-2,3-methylene-7α-fluoro-17,20-dimethylPGI₂ methylester Example 8-1 Preparation of1α-homo-2,3-methylene-5,6-dehydro-7-hydroxy-17,20-dimethylPGE₂ methylester 11,15-(t-butyldimethyl)silyl ether

Using the compound (840 mg) prepared in Reference Example 40, the aboveidentified compound (1.68 g) was prepared in the same manner as inExample 1-2.

¹ N-NMR(CDCl₃) δ-0.1-0.15(m, 12H), 0.75-0.93(m, 24H), 3.65(3,3H),4.10-4.20(m, 2H), 5.50-5.68(m, 2H)

Example 8-2 Preparation of1α-homo-2,3-methylene-5,6-dehydro-7-trimethylsiloxy-17,20-dimethylPGF₂ αmethyl ester 11,15-bis(t-butyldimethyl)silyl-9-triethylsilyl ether

Using the compound (1.68 g) prepared in Example 8-1, the aboveidentified compound (1.58 g) was prepared in the same manner as inExample 1-2.

¹ N-NMR(CDCl₃) δ-0.1-0.18(m, 12H), 0.50-0.68(m, 6), 0.72-1.00(m, 33H),3.65(s, 3H), 3.82-4.98(m, 1H), 4.07-4.21(m, 2H), 4.55-4.76(m, 2H),5.40-5.68(m, 2H)

Example 8-3 Preparation of1α-homo-2,3-methylene-5,6-dehydro-7β-fluoro-17,20-dimethylPGF.sub.2 αmethyl ester 11,15-bis(t-butyldimethyl)silyl-9-triethylsilyl ether

Using the compound (1.58 g) prepared in Example 8-2, the aboveidentified compound (1.22 g) was prepared in the same manner as inExample 1-3.

¹ N-NMR(CDCl₃) δ0-0.1(m, 12H), 0.50-0.70(m, 6H), 0.75-0.98(m, 33H),3.65(s, 3H), 4.03-4.18(m, 2H), 5.30-5.60(m, 3H) ¹⁹ F-NMR(CDCl₃, CCl₃ Fstandard) -168.4 ppm(m)

Example 8-4 Preparation of1α-homo-2,3-methylene-5,6-dehydro-7β-fluoro-17,20-dimethylPGF.sub.2 αmethyl ester 11,15-bis(t-butyldimethyl)silyl ether

Using the compound (1.22 g) prepared in Example 8-3, the aboveidentified compound (753 mg) was prepared in the same manner as inExample 1-4.

¹ N-NMR(CDCl₃) δ0-0.1(m, 12H), 0.75-0.93(m, 24H), 3.65(s, 3H),4.03-4.18(m, 2H), 5.30- 5.57(m, 3H) ¹⁹ F-NMR(CDCl₃, CCl₃ F standard)-168.1 ppm(m)

Example 8-5 Preparation of1α-homo-2,3-methylene-7α-fluoro-17,20-dimethylPGI₂ methyl ester11,15-bis(t-butyldimethyl)silyl ether

Using the compound (753 mg) prepared in Example 8-4, the aboveidentified compound (241 mg) was prepared in the same manner as inExample 1-5, followed by Example 1-6.

¹ N-NMR(CDCl₃) δ0-0.15(m, 12H), 0.70-0.95(m, 24H), 3.62(s, 3H),3.70-3.86(m, 1H), 4.12(m, 1H), 4.50-4.80(m, 2H), 5.27(dm, J=56.7 Hz),5.48-5.54(m, 2H) ¹⁹ F-NMR(CDCl₃, CCl₃ F standard) -182.9 ppm(m)

Example 8-6 Preparation of1α-homo-2,3-methylene-7α-fluoro-17,20-dimethylPGI₂ methyl ester

Using the compound (241 mg) prepared in Example 8-5, the aboveidentified compound (144 mg) was prepared in the same manner as inExample 1-7.

¹ N-NMR(CDCl₃) δ0.85-1.00(m, 6H), 3.65(s, 1.5H), 3.66(s, 1.5H),3.85-4.02(m, 1), 4.10-4.20(m, 2), 4.60-4.90(m, 2H), 5.26(dd, J=60 Hz,8.4 Hz, 0.5H), 5.54-5.76(m, 2H) ¹⁹ F-NMR(CDCl₃, CCl₃ F standard) -183.7ppm(dd, J=60 Hz, 8.1 Hz), -184.1 ppm(dd, J= 60 Hz, 8.1 Hz)

PREPARATIVE EXAMPLE 1 (GASTRIC CAPSULE)

50 mg of (1S*,3S*)-2,4-ethylene-7α-fluoro-17,20-dimethylPGI₂ methylester was dissolved in 10 ml of ethanol, and the solution was mixed with18.5 g of mannitol. The mixture was passed through a 30 mesh sieve anddried at 30° C. for 90 minutes. It was again passed through a 30 meshsieve.

To the powder thus obtained, 200 mg of Aerosil (microfine silica) wasadded, and the mixture was filled into 100 No. 3 hard gelatin capsulesto obtain gastric capsules each containing 0.5 mg of(1S*,3S*)-2,4-ethylene-7α-flouro-17,20-dimethylPGI₂ methyl ester.

PREPARATIVE EXAMPLE 2 (INJECTABLE SOLUTION)

0.5 mg of 2,4-methylene-7α-fluoro-17,20-dimethylPGI₂ methyl ester wasdissolved in 5 ml of ethanol, and the solution was sterilized byfiltration through a bacteria retention filter and be placed in 0.1 mlportions in 1 ml ampoules to obtain ampoules each containing 10 μg of2,4-methylene-7α-fluoro-17,20-dimethylPGI₂ methyl ester. Then, theampoules were sealed. The content of each ampoule after dilution to anappropriate volume, for example, by diluting with Tris hydrochloric acidbuffer solution of pH 8.6 to 1 ml, is suitable for use as an injectablesolution.

PREPARATIVE EXAMPLE 3 (FREEZE-DRIED PREPARATION FOR INJECTABLE SOLUTION)

A solution comprising 50 mg of2,4-methylene-7α-fluoro-17,20-dimethylPGI₂ sodium salt, 1.6 g ofα-cyclodextrin and 10 ml of distilled water, 10 mg of citric acid, 50 gof lactose and 800 ml of distilled water were added and dissolved. Thetotal volume was adjusted to 1 l with distilled water. Then, thesolution was subjected to sterile filtration in a conventional mannerand then be placed in 1 ml portions in ampoules, followed byfreeze-drying and sealing to obtain a freeze-dried preparation forinjectable solution.

We claim:
 1. A novel prostaglandin I₂ derivative of the followingformula (I) ##STR11## wherein R¹ is selected from the group consistingof C₁₋₁₀ alkyl, 1-methyl-3-pentenyl, 1-methyl-3-hexenyl,1-methyl-3-pentynyl, 1-methyl-3-hexynyl, cyclopentyl, cyclohexyl, andcyclopentyl substituted with methyl, ethyl, propyl, butyl, pentyl,phenoxy, trifluoromethyl, or trifluoromethylphenoxy; R² is a hydrogenatom, a C₁₋₁₀ alkyl group or a cation; each of R³ and R⁴ which may bethe same or different, is a hydrogen atom or a protecting group selectedfrom the group consisting of tiralkylsilyl, triarylsilyl,triaralkylsilyl, alkanoyl, tetrahydropyranyl, tetrahydrofuranyl,benzoyl, and methoxyethoxy; one of X¹ and X² is a hydrogen atom and theother is a halogen atom selected from a fluorine atom and a chlorineatom, and k, l, m and n are integers of from 0 to 6, respectively,provided that 0≦k+n≦4 and 1≦l+m≦6.
 2. The prostaglandin I₂ derivativeaccording to claim 1, wherein the halogen atom is a fluorine atom. 3.The prostaglandin I₂ derivative according to claim 1, wherein X¹ is afluorine atom, and X² is a hydrogen atom.
 4. The prostaglandin I₂derivative according to claim 1, wherein X¹ is a fluorine atom, X² is ahydrogen atom, R² is a group selected from a hydrogen atom, a C₁₋₄ alkylgroup and an alkali metal ion, each of R³ and R⁴ is a hydrogen atom, andR¹ is a C₅₋₉ linear or branched alkyl group.
 5. The prostaglandin I₂derivative according to claim 4, wherein R¹ is an alkyl group selectedfrom a n-pentyl group, a n-hexyl group, a 2-methylhexyl group and a1,1-dimethylpentyl group.
 6. The prostaglandin I₂ derivative accordingto claim 1, wherein k and n are integers of from 0 to 2, respectively,and l and m are integers of from 0 to 4, respectively, provided that0≦k+n≦2 and 1≦l+m≦4, and yet each of k+l+n and k+m+n is not more than 4.7. The prostaglandin I₂ derivatives according to claim 6, wherein k+n=1.8. The prostaglandin I₂ derivative according to claim 6, wherein k+n=0.9. The prostaglandin I₂ derivative according to claim 1, wherein thecycloalkylene group of the formula ##STR12## is a cycloalkylene groupselected from a cyclopropylene group, a 1,2-cyclobutylene group, a1,3-cyclobutylene group, a 1,2-cyclopentylene group, a1,3-cyclopentylene group, a 1,2-cyclohexylene group, a 1,3-cycloexylenegroup and a 1,4-cyclohexylene group.
 10. The prostaglandin I₂ derivativeaccording to claim 9, wherein k+n=1.
 11. The prostaglandin I₂ derivativeaccording to claim 9, wherein k+n=0.
 12. A prostaglandin I₂ derivativeselected from 2,3-methylene-7α-fluoro-17,20-dimethylPGI₂,4-homo-2,3-methylene-7α-fluoro-17,20-dimethylPGI₂,2,4-ethylene-7α-fluoro-17,20-dimethylPGI₂,2,4-ethylene-3α-homo-7α-fluoro-17,20-dimethylPGI₂,2,4-propylene-7α-fluoro-17,20-dimethylPGI₂,2,4-methylene-7α-fluoro-17,20-dimethylPGI₂,1α-homo-2,3-methylene-7α-fluoro-17,20-dimethylPGI₂, lower alkyl estersof these PGI₂ and sodium and potassium salts of these PGI₂.
 13. Aprostaglandin I₂ derivative selected from2,4-methylene-7α-fluoro-17,20-dimethylPGI₂, its methyl ester and sodiumsalt.